Britain’s decision to leave the EU has put the project of full European integration on pause, US President Barack Obama said on Tuesday.Obama told American media organisation NPR that Brexit has led to an over-reaction across the globe."There's been a little bit of hysteria post-Brexit vote, as if somehow NATO's gone, the trans-Atlantic alliance is dissolving, and every country is rushing off to its own corner. That's not what's happening," he said.He added that he would not “overstate” this hysteria.“I think that the best way to think about this is, a pause button has been pressed on the project of full European integration.”