Net immigration to the UK remains above 250,000 a year despite a small fall since the coalition Government took over, according to the latest independent figures.
Prime Minister David Cameron and Home Secretary Theresa May want to reduce the number to under 100,000 by the end of the parliament in 2015.
But the Office for National Statistics said estimated net migration to Britain - the number of people arriving for more than 12 months minus those leaving - in the year to September 2011 was 252,000, down only 3,000 on the previous year.
Long-term immigration fell from from 600,000 to 589,000, similar to the level it has been at since 2004, while emigration also dropped slightly from 345,000 to 338,000.
Of those coming to Britain, 250,000 did so to study.
The left-of-centre thinktank the Institute for Public Policy Research (IPPR) said net migration was effectively unchanged.
Associate director Sarah Mulley said: "The Government has so far made no progress towards meeting its target of reducing net migration to less than 100,000."
The Home Office said new rules had resulted in a big fall in the number of student visas issued to non-Europeans.
Its own research, covering the period to March 2012, showed student visas were down 62% in the first three months of this year compared with the same period in 2011.
Work and family visas were also down, the Home Office said.
Immigration Minister Damian Green said: "Our tough new rules are now making a real difference with a record 62% drop in student visas in the first quarter of 2012, and overall falls in work visas, family numbers and people settling.
"As these policies start to bite we are seeing an end to the years when net migration was consistently on the rise.
"But the hangover from the old system of weak controls means it is still too high and we will continue our programme of reforms to bring net migration down from the hundreds of thousands to the tens of thousands."
Migration Watch UK said the coalition needed to take "tough measures" to tackle the "unacceptable" figures.
Chairman Sir Andrew Green said: "You cannot expect to repair 15 years of mismanagement in 15 months, but it is worrying news that net migration is still running at a quarter of a million a year.
"There is no sign of any reduction from the huge numbers that developed under Labour."
Downing Street said the Government remained committed to getting net migration down below the 100,000 mark by the time of the next general election in 2015.
The Prime Minister's official spokesman said falls in specific categories of migration showed measures taken to tighten the controls were having an effect.
"That is evidence that the changes we are making to the rules are starting to have an impact," the spokesman said.
"It is still our intention to bring the levels of net migration back down to the tens of thousands. Clearly it is going to take some time."
Shadow home secretary Yvette Cooper said Mr Cameron was "not being straight" on immigration.
"The Tory-led Government is failing badly on its own immigration target to get net migration down to the tens of thousands by the end of this Parliament," she said.
"David Cameron said 12 months ago, 'No ifs. No buts. That's a promise we made to the British people.'
"Yet these figures show that promise is being broken and the net migration figure of 252,000 is barely changed in the last two years, even with the net rise in British citizens leaving the UK.
"Migration experts have said the Government does not have the policies to deliver on the target, so the Prime Minister is not being straight with the public on immigration. He should not make promises he can't keep on such an important policy area."