LATEST figures showing another surge in immigration put the nation's "common identity" at risk, Birkenhead MP Frank Field said today.

The last batch of official figures before voters go to the polls on May 7 revealed the Prime Minister has failed to deliver on his pledge to slash net migration to the tens of thousands before the general election.

There was a net flow of 298,000 migrants to the UK in the year to September, equal to the population of a city roughly the size of Nottingham and up from 210,000 in the previous 12 months, according to the Office for National Statistics (ONS).

The increase in net migration was driven by a "statistically significant" rise in immigrants arriving in the UK - up to 624,000 in the year to September from 530,000 in the previous 12 months.

Around 327,000 people emigrated from the UK in the same period.

Today's figures are the final nail in the coffin for the promise made by Prime Minister David Cameron and Home Secretary Theresa May to slash net migration to below 100,000 by the end of the current parliamentary term.

Mr Field said: "Every set of immigration data reinforces the need to control our borders.

"How can one expect a country to maintain its common identity and memories when in one year the population change alone was almost one million people – 327,000 leaving and 624,000 arriving?

"That’s over a one seventieth change in the entire population.

"At this rate in the next parliament it’ll be the equivalent to the whole of inner London’s population being changed."

There were also significant increases in immigration of non-EU citizens - up 49,000 to 292,000 - and European Union citizens - up 43,000 to 251,000.

Experts flagged another statistically significant increase in Romanian and Bulgarian citizens arriving in the UK - up to 37,000 from 24,000 in the previous 12 months.

Around 271,000 people came to the UK for work, up 54,000 on a year earlier, while immigration for study rose from 175,000 to 192,000.Of these, 27,000 were coming for work, a rise of 10,000 on the year ending September 2013, the ONS added.

Madeleine Sumption, director of the Migration Observatory at the University of Oxford, said: "UK job growth is likely to be a key factor behind the recent increases.

"If the UK's economic performance compared to the rest of the EU had been poor, then we might well have seen net migration fall, but that has not happened.

"Rising work-related migration from outside the EU has also contributed."

Sunder Katwala, director of the British Future think-tank, said: " The ONS statistics have become a quarterly reminder to the public of why they don't trust politicians on immigration, thanks to the net migration target.

"If the Prime Minister remains in denial about the broken target, he is setting himself up for five more years of failure. It is already clear there is next to no chance of meeting the same target in the next parliament either."

Deputy Prime Minister Nick Clegg said the Tories would have to "suffer the embarrassment of having ... failed spectacularly to deliver".

"I said to David Cameron he shouldn't make the commitment because it was inevitable he was going to break it because you can't control the net figure," he said on his weekly LBC radio phone-in.

Immigration and security minister James Brokenshire said: "Uncontrolled, mass immigration makes it difficult to maintain social cohesion, puts pressure on public services and can force down wages.

"That's why this Government is working to reduce net migration - and why today's figures are clearly so disappointing.

"As we have said for some time, we have been blown off course by net migration from within the EU, which has more than doubled since 2010.

"That's why we need to continue to crack down on the abuse of EU free movement and continue our reforms to make our welfare system fairer and less open to abuse.

"We have scrapped housing benefit for EU jobseekers, have limited benefits claims for EU migrants with no prospect of a job - and the Prime Minister has set out our plans for further reform."

He added: "The immigration system we inherited was open to widespread abuse and gave little consideration to whether migrants could support themselves or contribute to the UK when they arrived.

"We are building a system that is fair to British citizens and legitimate migrants and tough on those who abuse the system or flout the law - but we know there is much more to do."