"Yes, a strong Europe is very, very important to me as president of the united states," Trump told reporters at a joint news conference with Italy's Prime Minister Paolo Gentiloni.

"And it is also in my opinion -- in my very strong opinion -- important for the United States. We want to see it. We will help it be strong."

Trump's past comments predicting that other countries "will leave" the EU after Britain voted to do so last year rankled European leaders.

European Commission President Jean-Claude Juncker even responded with a joke he was ready to encourage US independence movements if Trump failed to tone down his Brexit support.

But more recently, Trump has endorsed the European bloc, which describes itself as a bastion against the nationalistic rivalries that so often tore it apart in wars in past centuries.

Early this month, the US president told the Financial Times newspaper he thought the European Union was "getting their act together" -- though he maintained Brexit would be "really, really good" for the Union and for Britain.