The Serious Fraud Office (SFO) has announced that chief operating officer Mark Thompson is to take the reins as interim director.

Current director David Green QC departs this month.

Although a successor to Green has been appointed, they cannot take up their post immediately. The SFO said the new chief’s identity will be announced ’when it is possible to do so’.

Thompson, who takes charge on 21 April, said: In the meantime it’s important that the SFO pursues its cases with vigour and discharges its legal and corporate obligations responsibly. My role will be to ensure we continue to do this, and to ensure a smooth transition when the new director arrives.’

Green, who has secured several notable deferred prosecution agreements during his directorship, said last month that under his tenure the office had shifted from having a reputation of being ‘anxious to do a deal’ to being able to make a ‘clear offer’ underpinned by legislation to companies who admit to wrongdoing.

He added that although he is not minded to give advice to his successor, he hoped the option of a DPA, which can at times come with a discount of up to 50% on penalties, would be retained

Green has been tipped for a move to a US firm when he departs.

Alison Geary, Counsel in UK investigations & criminal litigation practice of international firm WilmerHale, said: ’This announcement sparks more questions than it answers. Clearly the permanent candidate is external to the SFO. It is difficult to tell where this new candidate is coming from, why their name cannot be revealed or how long it will be before they are in place. The SFO is, once again, left in limbo.’