Seven Russians now under sanctions were awarded controversial “golden visas” by the UK after Vladimir Putin’s regime first invaded Ukraine in 2014, the government has admitted.

The government closed the “tier 1 investor visa” scheme in February amid the build-up of Russian forces on Ukraine’s border as it prepared to broaden its occupation beyond Crimea, which it annexed in 2014.

Since the invasion, sanctions targeted at many of Russia’s richest businessmen have become a key part of the response by the UK and its allies.

The measures have also prompted awkward questions for the government, with critics accusing it of offering an open door to kleptocrats and oligarchs, who in some cases are thought to have expropriated wealth from the Russian state on a massive scale. Much of that wealth has been used to buy luxury property in London.

The golden visa scheme allowed people with at least £2m in investment funds and a UK bank account to apply for residency rights, along with their family. Before 2018 it is thought that minimal checks were carried out on investors or the source of their wealth.

The government revealed that 10 Russians who received golden visas are now subject to sanctions, an increase from the eight previously admitted, in a written answer to a question from Stephen Kinnock, Labour’s shadow immigration minister.

Kevin Foster, a junior Home Office minister said seven of those 10 Russian nationals “either obtained an initial grant of leave or obtained further leave via the route after 2014”.

The government declined to name the people who received the visas, despite demands from Labour and Spotlight on Corruption, a campaign group.

In 2014 David Cameron, then prime minister, said Russia must “choose the path of diplomacy and de-escalation, or face increasing isolation and tighter and tighter sanctions”. However, the latest data suggested that the government continued to wave through visas for Russian nationals now considered by officials to play key roles in supporting Putin’s regime.

“Putin’s invasion of Crimea should clearly have been a fork in the road for how the British government viewed Russian oligarch investors,” said Kinnock. “It therefore beggars belief that – even after the threat posed by Putin to western security and British interests had been exposed – the Conservative government continued to award grants of tier 1 (investor) leave to seven of Putin’s cronies who would later be sanctioned.”

Spotlight on Corruption said the latest revelation made it even more urgent that the government release a 2018 report on the golden visa scheme. A minister last month committed to publish it, but the government has not yet done so.

Susan Hawley, the group’s executive director, said: “This is compelling evidence of the frankly shocking complacency in the UK government about Russian money coming to the UK even after Russia started its aggression against Ukraine in 2014.

“The golden visa regime looks increasingly like a state-sponsored scheme to enable kleptocracy. The lessons must be learned for the UK visa regime across the board.”

A Home Office spokesperson said: “We have made it clear we will not tolerate abuse of our immigration system and we have closed the tier 1 (investor) route with immediate effect to ensure that those who have profited from dirty money cannot gain access to the UK.

“We want to make it clear that the UK is no safe haven for those who enable the Putin regime. By implementing the largest and strongest sanctions package in the UK’s history, we are continuing to crack down on these individuals and making sure they pay the price.”