The countdown to the final closure of Sangatte began on Thursday as UK officials processed the first group of refugees to be given work status in Britain.

Conservatives have attacked a deal allowing Iraqi and Afghan asylum seekers four-year permits in return for the controversial Red Cross centre's closure.

Ministers have hailed the processing of the first residents for whom the UK has agreed to take responsibility as "groundbreaking".

"As a result of the unique and groundbreaking deal agreed with the French government this week, the countdown to the final closure of Sangatte begins today," said immigration minister Beverley Hughes.

"These people will be brought to the UK over the next few weeks, having been fully security checked and temporarily accommodated while they are helped to find work, so that they can fully contribute to our economy, support themselves and pay taxes, rather than claiming asylum."

Shadow home secretary, Oliver Letwin, has accused the government of complacency in the face of a "growing asylum disaster''.

Simon Hughes MP, the Liberal Democrat home affairs spokesman, said the government was offering "a short-term fix, not a long-term solution".

"An opportunity to use Sangatte as a pilot scheme for sharing responsibility for asylum seekers across the European Union has been missed," he said.

"This deal runs the risk of confusing those who come to the UK as asylum with those who come as economic migrants. We must ensure that those with a genuine claim for asylum are able to put their case."