Image caption Nearly half a million immigrants arrived in the UK last year

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 change in the number of people who left Britain. In the year to September 2012, 342,000 moved abroad. But fewer people left the UK in the year to December 2012.

Over the same period, the number of immigrants arriving in the country remained virtually unchanged. The difference between these two factors meant that net migration rose - although it did not climb back above the level it was at in December 2011.

Analysis Today's figures show how tough the government's self-imposed net migration target could become. The news is not all bad. The detail shows that immigration itself is down on where it was when the coalition came in - now sitting at under half a million people a year. But the problem for ministers is that they can't control all forms of immigration and emigration - and fewer British and EU citizens are leaving. If fewer people leave, then the net migration balance can rise, even if the number of immigrants declines. So if the government is going to hit its target, it may need to find more tools to increase departures while maintaining pressure on arrivals. And that's why many experts on different sides of the political and policy debate argue that the net migration target isn't a sensible measure of how well the system is being managed.

'Out of options'

Immigration minister Mark Harper said net migration was however down by a third since its peak in 2010.

He added that a new immigration bill coming into force in the autumn would make it more difficult for people to come into Britain if they had no right to do so and would make it easier to remove people who were not entitled to stay in the country.

"We are committed to bringing net migration down from the hundreds of thousands to the tens of thousands," Mr Harper said.

"We are working across government to protect public services and ensure our welfare system is not open to abuse."

Shadow immigration minister Chris Bryant said the figures were "a blow" to the home secretary.

"Theresa May's focus on net migration, which has gone wrong in these figures, has also meant the government is failing badly on illegal immigration, which is a major concern to the public and is getting worse and worse with fewer people being stopped at the border, absconsions up and deportations down.

"Immigration needs to be controlled, but we must recognise there is immigration that works for Britain and immigration that doesn't."

But the pressure group Migrationwatch UK said that the detail of the latest figures showed the government was succeeding in cutting immigration from outside the EU - and that further reductions in net migration could come by ensuring that people leave when they should.

Sir Andrew Green, Migrationwatch's chairman, said: "It is far too early on the basis of one quarter's figures to call this a setback to the government's policy. Student interviews and measures to ensure that students leave when they should will make a substantial difference."

Sarah Mulley, of the centre-left think tank, the Institute for Public Policy Research, said the statistics suggested the government was running out of options to meet its target.

"Recent declines have been driven in large part by falling numbers of international students, which has come at a high economic cost, but this trend now appears to be levelling off," she said.

Other figures released in the report include: