UK's Duncan Smith brushes Obama Brexit comments aside

U.S. President Barack Obama's warnings about Brexit are less worrying given the president will soon leave office, the U.K.'s former work and pensions secretary told CNBC.

Obama urged European unity last month ahead of Britain's June referendum on European Union (EU) membership. The president warned that Britain would go to the "back of the queue" if it went solo, saying a new trade deal could take up to 10 years to seal.

However, Britain's former work and pensions secretary and Conservative politician Ian Duncan Smith told CNBC that Obama's comments are "not at all" concerning.

"First of all, he won't be there," he told CNBC.

"And secondly the queue consists of one trade deal called the European trade deal."

The U.S. and European Union are currently negotiating terms of the bilateral Transatlantic Trade and Investment Partnership (TTIP) which one independent study by the Centre for Economic Policy Research claimed could boost the EU economy by 119 billion euros ($134 billion) annually, with the U.S. economy benefitting by up to 95 billion euros per year.

A British exit from the EU would effectively exclude Britain from the deal.

Still, Duncan Smith insisted that U.K.-U.S. relations won't fail to be a priority by the U.S. administration.

"There are plenty of decisions being made by people in America who don't agree with that. The fact is we are, you know, one of the biggest partners in trade with the USA, we're one of the biggest defense partners of the USA...We'll go on doing that and we run a trade balance with the U.S.A. actually."

Obama did face criticism following his speeches for meddling in domestic affairs, though a number of politicians and running presidential candidates have also weighed in on the upcoming referendum.

Donald Trump, who is currently the front-runner for the Republican presidential nomination, said he thought Britain would be better off outside of the EU.

"They told us we had to join the euro otherwise somehow we would be an economic basket case on the edge of Europe with unemployment," Duncan Smith said. "Actually the opposite has happened."

"By not during the euro … European Union that joined the euro, they're all a basket case, they have problems whereas we are seeing some growth, and we're seeing the creation of jobs," he added.

The unemployment rate in the euro zone was last measured at 10.2 percent, with countries like Greece and Spain clocking jobless rates of over 20 percent. The U.K. meanwhile, is tracking a 5 percent unemployment rate – one of the lowest in Europe.

Britain's EU referendum will be held on June 23.