Washington, Oct 19 (IANS): The US President said on Wednesday that a congresswoman had lied about his conversation with the widow of an American soldier killed in an ambush early this month in the northern African nation of Niger.

Donald Trump took to Twitter to slam Republican Frederica Wilson, a Democrat from Florida, who said the head of state had told US Army Sgt. La David Johnson's widow that her husband "knew what he signed up for... but when it happens it hurts anyway."

"Democrat Congresswoman totally fabricated what I said to the wife of a soldier who died in action (and I have proof). Sad!" Trump tweeted.

Wilson, meanwhile, told CNN Wednesday that she also had her own evidence.

"I have proof, too. This man is a sick man," Wilson said in response to Trump's tweet, adding that Johnson's widow was in tears after the phone call and that the president did not even know the soldier's name.

The body of the army sergeant, one of four US servicemen who died in an October 4 ambush in Niger, was received with honors at Miami International Airport at a ceremony attended by authorities, the soldier's widow and other family members.

Wilson said she was with Johnson's widow when she received the phone call from Trump and heard a portion of the conversation.

This latest controversy comes just days after Trump sparked outrage by saying his predecessors had not made phone calls to the families of soldiers killed in combat.