UKIP Defence Spokesman Mike Hookem has called President Obama "a hypocrite who doesn't know his history" after the American leader used the two world wars as an excuse to interfere in the EU referendum.
Mr Obama said he had a right to tell the British people how to vote because the USA and Europe's history were "intertwined".
But Mr Hookem said there was something "sick" about using the dead in war graves to argue for Britain to be governed by Brussels.
"To use the sacrifice of those who gave their lives in the fight against a foreign power who had a desire to rule Europe somehow seems sick," the former Commando said.
He also pointed out that "The USA came into the war after Japan bombed Pearl Harbour, not because of Nazi Germany.
"If he's going to wade in telling the British people how to vote, particularly for the kind of political union he would never accept, he should get his facts straight."