Levels of immigration into the UK could be about to hit their highest ever point, as the latest figures are due to be released this morning.
Net migration - the difference between the number of people entering and those leaving - reached a record 320,000 in June 2005.
Last year, the difference stood at 318,000, meaning even just a small increase could push it over that mark.
Figures are also expected to show that the number of people living in Britain who were born abroad has topped eight million for the first time.
It is expected to spark fresh scrutiny of the Conservatives' pledge to reduce net migration to below 100,000.
A survey released last week found that a third of British people believe migration is the most important issue facing the country - with claims that the government has "no long-term plan" to meet their stated target.
The figures - which reflect legal migration - come amid the ongoing migrant crisis at Calais, which has seen thousands of people try to sneak into Britain by breaking into the Channel Tunnel or jumping on to lorries crossing the water.
The situation in France is part of a wider problem affecting most of Europe, as large numbers of migrants flee poverty and war in North Africa and the Middle East.
Earlier this week, ministers unveiled the details of their plans to tackle immigration, which include jailing illegal immigrants caught working.
A business leader has accused the government of harming businesses by creating what he described as ad hoc immigration policy.
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."