The Ministry of Justice says it is 'disappointed' that its suppliers have been unable to fully resolve the IT failure that has significantly disrupted the justice system over the past few days.

Last night the department once again apologised to those affected by the 'network issues'. A spokesperson said: 'The urgent work we have been carrying out with our suppliers has led to significant improvements today, but this work is ongoing and we have contingency plans in place.

'While services have continued to operate and alternative network access is now in place for most, we know how frustrating this is for anyone affected and we are disappointed that our suppliers haven’t yet been able to resolve the network problems in full. We continue to work with them to return services to normal.'

The issue was widely reported across national media on Wednesday, and shadow justice minister Yasmin Qureshi secured an urgent question in the House of Commons on the issue. This will be debated following Prime Minister's Questions on Wednesday.

The MoJ has reiterated that the problems, which included practitioners being unable to send or receive messages through the government's secure criminal justice email system, have not been caused by malicious cyberactivity and no data has been lost.

The problem appears to be in the main MoJ network, which is also used by the department's other agencies and arms-length bodies, including HM Courts & Tribunals Service users. Emails and internet access have continued to work across the estate via Wi-Fi on mobile devices, but not directly wired devices.

Network access was restored to around 180 further MoJ sites yesterday. The ministry is working with its suppliers, Microsoft and Atos, to establish other ways to access the network, including rerouting traffic and installing additional capacity.

The Legal Aid Agency said it does not expect the number of rejected claims to increase as a result of the problems. But advocates are advised to provide copies of court attendance notes and, when they submit their claim forms, indicate if they had any trouble signing into court.

The Criminal Bar Association described the agency's statement as 'underwhelming'. The association said on its website: 'If counsel state that they were present to conduct the hearing - how else could it have taken place - in these particular circumstances the advocate’s word and signed claim form should be accepted for very obvious reasons.'

Elsewhere, the ministry says it has not received reports of prisoners' releases being delayed.

The government is spending £1bn to modernise the courts system. However, the ministry insisted that the network issues are unrelated. It said its online public-facing services, such as online divorce and probate applications, and internal casework systems, have continued to work throughout the disruption. The Common Platform system is still in its testing phase and has not been affected.

Today Labour MP Yasmin Qureshi asked the justice secretary in the House of Commons chamber to make a statement on the IT system failure.

Justice minister Lucy Frazer apologised to those who affected by the 'intermittent disruption which was caused by an infrastructure failure in our supplier's data centre'.

Frazer said: 'The issue has been that some of our staff in courts and tribunals, the Legal Aid Agency, probation, and MoJ HQ have been unable to log onto their computers. But we have contingency plans in place to make sure the trials can go ahead as planned.'

Frazer said the prison service has not been affected and stressed that 'criminals have not gone free as a result'. Permanent secretary Richard Heaton will be meeting the chief executive of Atos, the MoJ's supplier, this afternoon.