An estimated 500 elite Afghan soldiers who fought alongside the British are expected to become eligible to come to the UK after a previous decision rejecting their applications was overturned.

Fresh information has been discovered in about a quarter of the 2,000 rejected cases proving that the at-risk veterans were paid and employed by the UK government in Afghanistan, despite previous claims that no such evidence existed. A review had been launched by the Conservatives in February.

Luke Pollard, the minister for the armed forces, told the Commons on Monday that the emergency reassessment reflected “the problems that have dogged the Afghan resettlement scheme under the previous government”.

Pollard said there had been 2,000 cases in which there had been “an inconsistent approach” to decision taking. Of the cases that had been reviewed under Labour, the minister said “we are expecting an overturn rate of approximately 25%”.

Some of the Afghans have been in hiding from the Taliban, who have been in charge of Afghanistan since the western withdrawal in summer 2021, while a couple of hundred fled to Pakistan where they are at risk of deportation. Six are said to have been murdered for having collaborated with the British.

They include members of the elite Afghan 333 and 444 units, known as the Triples, who fought alongside and worked closely with British forces, including the SAS, during more than a decade of UK military involvement in Afghanistan.

The SAS also had a veto on whether Afghan veterans could come to the UK, but defence sources indicated this was not the reason for the cases being overturned – rather, it was the belated discovery of fresh financial records.

Pollard said: “Officials have now confirmed that there is evidence of payments from the UK government to members of Afghan specialist units, including ‘CF triple three’ and ‘ATF triple four’, and that for some individuals this demonstrates a direct employment relationship.”

There had been concern over a conflict of interest, because a public inquiry is examining allegations that the SAS carried out 80 unlawful, summary killings in Helmand province between 2010 and 2013. Afghan veterans may in theory be able to give evidence that contradicts the SAS position.

In February the then minister for the armed forces, the Conservative James Heappey, said “we do not hold comprehensive employment or payment records” for members of the Afghan special forces. He said they had reported directly to the former government of Afghanistan.

Pollard, his Labour successor, said he had seen “no evidence” suggesting there was a deliberate effort to prevent eligible Afghans from coming to the UK. Conservative ministers had acted “in good faith”, Pollard said, and he placed the blame on problems with information flows between government departments. “I am clear that this sort of systems failure is not good enough,” he added.

The unexpectedly rapid takeover by the Taliban after the US-led withdrawal led to the UK announcing several schemes to allow Afghans who had helped the British to come to the UK. Since the withdrawal, 12,874 Afghans have been granted indefinite leave to remain in the UK – including about 400 members of the triples.

In opposition, Labour had campaigned for the Conservative government to reassess cases involving the Afghan veterans. Pollard told MPs that “it should not have taken this long” to start overruling decisions, and that the review announced in February should have been completed before the July general election.