Net migration to the UK increased in the year ending December 2012, the Office for National Statistics says.
Latest figures show net migration rose to 176,000 – up from 153,000 people in the year to September 2012.
The increase appears to buck the trend of a decline in net migration – the difference between the number of people coming to and leaving the country.
Prime Minister David Cameron wants to get UK net migration below 100,000 before the next election in 2015.
The increase was driven by a drop in the number of migrants leaving Britain, which fell from 351,000 to 321,000 in the year to December 2012, the ONS found.
Over the same period, the number of immigrants arriving in the country dropped from 566,000 to 497,000, figures showed.
The BBC’s home affairs correspondent Dominic Casciani said the reasons for the rise were complex and partly related to the fact that fewer people were emigrating from the UK than the government expected.
If fewer people leave the UK, then the net migration balance can rise, even if the number of immigrants arriving declines or remains static, he added.
See on www.bbc.co.uk