A defiant Jacqui Smith brushed off pressure for her to quit as Home Secretary after Conservatives yesterday accused her of "blunder, panic and cover-up" over the granting of clearance for up to 5,000 illegal immigrants to work as security guards.
The Redditch MP was forced to make a statement to the Commons after it emerged she had known about the problem for at least four months before the news became public last weekend.
In her first major political test since becoming Home Secretary, she refused to apologise after leaked emails - which listed Birmingham MP and Immigration Minister Liam Byrne among the recipients - revealed she decided to keep the problem quiet.
The documents appear to show that she accepted advice from officials that a news blackout should be imposed on the story for fear it could spark negative headlines.
One email in August, sent from Ms Smith's office to officials and Ministers including Mr Liam Byrne (Lab Hodge Hill), warns that "the lines we have" - which means the comments the Government would give to the media - are "not good enough".
Ms Smith received support from Labour MPs yesterday but will continue to face pressure from the Conservatives.
Shadow Home Secretary David Davis accused her of putting "avoiding political embarrassment" ahead of tackling the problem.
During the Commons debate, he sarcastically asked her: "Is this really the first opportunity you have had to tell the House about this?"
He added: "The response of the Home Office so far has been blunder, panic and cover-up. The Prime Minister spoke of frank and candid government, yet in one of her first actions as Home Secretary, she put avoiding political embarrassment ahead of solving the problem and informing the public."
Ms Smith - who has received Mr Brown's backing - admitted 12 people who did not have the right to work in Britain had ended up working as security guards for the Metropolitan Police.
One of these was employed guarding official cars, including the Prime Minister's vehicle.
But Ms Smith denied there had been any cover-up over the employment of illegal immigrants in the security industry, insisting Ministers had taken "robust action".
The Government had wanted to wait until it had all the facts before making any announcement, she said.
She told MPs: "My approach was that the responsible thing to do was to establish the full nature and scale of the problem and take appropriate action to deal with it, rather than immediately to put incomplete and potentially misleading information into the public domain."
She stressed it was the "legal duty" of all employers to ensure their employees were entitled to work in the UK.
The Security Industry Authority, which has licensed applicants for security posts since 2003, had "not failed to do anything that it was obliged to do in law", she said.
She told MPs that from July, every non-European applicant had had their right to work in the UK checked and from October the SIA had required "new and tighter" identity checks.
Reports at the weekend revealed some illegal immigrants given licences by the SIA ended up working for the Metropolitan Police. Others reportedly found employment in Whitehall and at ports and airports.
The SIA, which reports to the Home Office, said it was not its role to check the immigration status of foreigners applying for clearance.