Labour would give the UK Border Agency the power of arrest to prevent illegal immigrants escaping, under new proposals outlined today by the shadow home secretary.
Labour's Yvette Cooper told Politics Home that the Government was failing to cut the most damaging forms of immigration as illegal entry is not affected by its key target.
UKBA compliance officers would be able to arrest suspected illegal immigrants under Labour's proposals, Ms Cooper said, while an enforcement taskforce would be formed.
Illegal immigrants from Eritrea being searched in France, after attempting to enter the UK
"The starkest example of the most damaging immigration is illegal immigration - yet here too little action is being taken," Cooper said.
"With big drops in the number of people being deported or refused entry, and a growing backlog of suspected illegal cases not being followed up, it seems the problem is getting worse.
"And as enforcement resources are being heavily cut, UKBA doesn't have the flexibility or powers it needs."
UKBA compliance officers, who visit universities, colleges and other organisations, currently have no powers of arrest and are able to take little or no action.
A spokesman for the Home Secretary said: "Yvette Cooper and the Labour Party have no credibility on immigration whatsoever.
"That will remain the case until they support the Government's policies, which have reduced net immigration by a quarter in the last year."
Cooper conceded that "Labour was too slow on immigration" but said the Tories risk being "too simplistic".
She said the Home Office was too heavily focused on its net migration target of fewer than 100,000 people a year from outside the EU by the next general election in 2015.
"Bizarrely it makes it a sign of success if more Brits move abroad, measuring as it does the difference between immigration and emigration, and indeed the recent drop in the net migration figure was accounted for almost entirely by fewer Brits returning home, more Brits leaving and fewer foreign students," she said.
Net migration to the UK went down by 25% to 183,000 in the year to March, according data from the Office of National Statistics.
The period saw the number of people coming to the UK fall to 536,000, while the number of people leaving the country rose 353,000.
Cooper's article comes after Ed Miliband promised new measures to prevent British people being "locked out" of jobs by foreign workers, including forcing firms to declare if they employ high numbers of immigrants.
Overseas-only employment agencies would be banned and an early-warning system set up to highlight areas where locals are "dominated" by an influx of overseas labour under the proposals.
Last week, Home Secretary Theresa May said thousands of applicants for visas to study in the UK are to be subjected to interviews in a bid to crack down on bogus students.
The announcement came in a speech in which Mrs May rejected claims that the Government's controversial clampdown on student visas was damaging business and universities by making it harder for non-EU nationals to come to the UK to learn.