Anti-enforcement injunctions

Pursuant to section 37(1) of the Senior Courts Act 1981, the English court has the power to grant anti-enforcement injunctions (AEI) and anti-suit injunctions (ASI). An AEI is a court order restraining a party from enforcing (or seeking to enforce) a judgment or arbitral award in a foreign jurisdiction. An ASI is a court order that restrains a party from commencing or continuing proceedings in another jurisdiction. In the landmark decision of Federal Republic of Nigeria and another v Williams [2025] EWHC 2217 (Comm), Mr Justice Henshaw granted, for the first time, an AEI to restrain the defendant from enforcing an earlier judgment of the Commercial Court. 

AEI applicable principles

The principles applying to AEI were summarised by Mr Justice Henshaw in Google v Tsargrad [2025] EWHC 94 (Comm) as follows:

• The fundamental question for the purposes of section 37(1) of the Senior Courts Act 1981 is whether it is just and convenient to grant an injunction.
• In principle, the enforcement of a judgment obtained in breach of an exclusive jurisdiction clause or an arbitration agreement can be restrained by injunction. The order operates in personam: like an ASI, it is directed to the party, not the foreign court or courts.
• There is no distinct jurisdictional requirement that the case be exceptional.
• However, AEI are rarely granted, because delay and/or comity considerations usually make it inappropriate to grant such an injunction.
• As to comity, an AEI (like an ASI) has the effect of indirectly interfering in the processes of a foreign court, and hence a strong step for which clear justification must be required.
• The fact that the foreign proceedings were brought in breach of the respondent’s obligations under an exclusive jurisdiction clause or arbitration agreement is capable of amounting to such a justification.
• It would be particularly intrusive and inconsistent with comity to grant an injunction indirectly preventing enforcement by and in the territory of a foreign court which has already proceeded to judgment. Moreover, such an injunction would be liable to result in the resources and time of the foreign court, as well as the respondent, having been wasted, providing a further strong reason against the grant of such relief.
• Where an AEI prevents enforcement in one or more third countries, the general point about indirect interference with a foreign court applies, in relation to both the foreign court which gave judgment and the putative enforcement court. However, if the injunction is sought before or at a very early stage of those enforcement proceedings, concerns about waste of resources and time of the enforcement court should not arise. Such concerns may still arise in relation to the court which gave judgment and in relation to the respondent, but that will depend on the circumstances. The position may be different, for example, if the injunction is not designed to prevent enforcement of the judgment in its entirety, and hence does not render the proceedings leading to judgment a waste of time and resources.
• Where the respondent seeks to enforce in a third country, it has been stated that the right to enforce should depend primarily on the law of the enforcement court, which the English court should not pre-empt by granting an injunction. However, in the case of an ASI, it is not regarded as a bar to injunctive relief that the overseas court ought instead to be left to make its own jurisdictional decision (applying its own rules as to the effect of exclusive jurisdiction clauses and arbitration agreements). It is arguable that it is no more intrusive indirectly to interfere with an overseas court’s enforcement of a foreign judgment than with an overseas court’s adjudicative jurisdiction over a dispute. In any event, there is a cogent argument that an applicant who has contracted for an exclusive jurisdiction clause or arbitration agreement has a prima facie entitlement not to be troubled by either substantive or enforcement proceedings elsewhere, and accordingly to seek to hold the respondent to its contractual promise.
• It is relevant to consider whether there is a good reason for the applicant not having applied sooner for injunctive relief or whether the applicant was simply hoping to have two bites at the cherry.
• Delay is an important, and sometimes decisive, factor against the grant of an injunction, but it is not necessarily a bar to relief. Its weight will depend on all the circumstances. In assessing the circumstances, account will need to be taken of the considerations identified above. The relevant circumstances will include whether the AEI seeks to prevent enforcement within the territory of the judgment court or only elsewhere; whether the injunction seeks to prevent enforcement of the judgment in its entirety; whether (if obeyed) it will result in the proceedings leading up to judgment having been a waste of time and resources; and whether there is a satisfactory explanation for the applicant not having applied sooner for injunctive relief.

Federal Republic of Nigeria and another v Williams

In earlier proceedings, Moulder J granted Dr Williams default judgment for $15m against Nigeria. Nigeria’s application to have the judgment set aside was dismissed. Dr Williams then commenced proceedings in New York seeking to enforce the default judgment there. In the meantime, Nigeria commenced fresh proceedings in the English Commercial Court to have the default judgment set aside on the grounds that it had been obtained as a result of fraud. Dr Williams applied to have Nigeria’s application struck out as an abuse of process. However, Henshaw J dismissed Dr Williams’ application and subsequently granted Nigeria an AEI restraining Dr Williams from enforcing the judgment in New York pending the determination of Nigeria’s application to set aside default judgment. Nigeria obtained the AEI on the ground that enforcement of the default judgment in New York before the outcome of the English proceedings would be ‘vexatious and oppressive.’

Henshaw J held that there was no principled reason why an AEI could not be granted to prevent Dr Williams from seeking to enforce an English judgment. Henshaw J explained that the relevant test to determine whether to grant an AEI on the ‘vexatious and oppressive’ ground is the ‘high probability’ test, which means that the applicant must show a high probability that it will succeed in establishing its case for a final injunction at trial. Henshaw J also explained that the ‘high probability’ test is appropriate because an interim injunction will often be decisive of the issue by determining, in practice, where the substantive dispute is tried. The position may be different where the order is granted on a temporary basis in order to ‘hold the ring’ pending a further hearing or trial and the interim order will not in practice be determinative of the outcome, in which circumstances an American Cyanamid approach may well be appropriate.

Henshaw J held that there was a compelling case that enforcement of the default judgment in New York prior to the determination of the English proceedings would be vexatious and oppressive. He explained that the AEI would merely suspend the New York proceedings pending the outcome of the English proceedings. However, applying the ‘high probability’ test on the current evidence, it was highly probable that Nigeria would succeed at trial in establishing that an AEI would be granted. Henshaw J also explained that the interests of justice require the grant of an AEI because if Dr Williams successfully enforced the default judgment in New York, any subsequent judgment in Nigeria’s favour in the English proceedings may be rendered nugatory. Furthermore, if Dr Williams suffered delay in enforcing the default judgment, interest will accrue, and Dr Williams may be able to enforce the cross-undertaking provided by Nigeria. Finally, Henshaw J found that there was no issue of comity because the AEI sought to protect the integrity of the English court’s own process and to prevent its own judgment from being used as an instrument of fraud.

The decision in Federal Republic of Nigeria v Williams confirms that AEI can be used not only to restrain foreign enforcement of foreign judgments, but also to suspend enforcement of English judgments abroad where necessary to protect the integrity of domestic proceedings. The decision highlights both the availability and the limits of AEIs: applications must be made promptly, supported by strong evidence, and justified in accordance with the principle of comity. The decision also reinforces the importance of carefully considering interim relief strategies where parallel enforcement proceedings are in play. Ultimately, while AEIs remain exceptional, the decision in Federal Republic of Nigeria v Williams demonstrates that the English courts are prepared to intervene when enforcement abroad would undermine justice at home.

Masood Ahmed is an associate professor at the University of Leicester and a member of the Law Society’s Dispute Resolution Advisory Committee. Osman Mohammed BA (Political Science and International Relations), University of Birmingham, also contributed to this article