New figures set to show net migration at record levels
New figures will confirm today whether a key immigration measure is at record levels.
The last set of data showed net migration to the UK - the difference between the number of people entering and the number leaving - stood at 318,000 in 2014.
Today's report would only need to show a modest increase to surpass the highest figure on record, which was 320,000 in the year ending June 2005.
It will bring fresh scrutiny of the Tories' ambition to bring net migration below 100,000.
Statistics are also expected to show that Britain's foreign-born population has surpassed eight million for the first time.
Earlier this week, ministers announced new details of the upcoming Immigration Bill.
Illegal immigrants caught working in the UK could face up to six months in prison and late-night takeaways and off-licences facing closure if they are found employing them.
It comes in the wake of the crisis at Calais, which saw thousands of attempts by migrants to cross the Channel throughout the summer.
The situation at the port in northern France is part of a wider influx of people into Europe from North Africa and the Middle East.
Last week, a survey found that one in three Britons believes immigration is the most important issue facing the country.
There were claims the Government currently has "no long-term plan" to meet the net migration target ahead of today's figures.
Sunder Katwala, director of thinktank British Future, said: "This Government was elected on the importance of setting out a credible long-term plan and delivering it.
"Immigration policy should be no different - setting sensible and achievable controls on migration in a way that is consistent with the economic recovery."
Simon Walker, director general of the Institute of Directors, said:"By announcing polices on the hoof every time new figures come out, the Government betrays its lack of a long term plan on migration.
"Scrabbling around to find measures to hit a bizarre and unachievable migration target is no way to give British businesses the stable environment they need."