WASHINGTON • President Donald Trump has not decided if the United States will remain a part of the Paris climate accord, Secretary of State Rex Tillerson said, as pressure mounts from Pope Francis, European leaders and Democratic lawmakers at home for the US to stay in the historic pact to address global warming.

Mr Trump's decision will not be made until after he returns from his first foreign trip as President, Mr Tillerson said on Wednesday on Air Force One on the way from Rome to Brussels. "The President indicated we are still thinking about that. He has not made a final decision."

The delay has created an opening for foreign and religious leaders, who are imploring Mr Trump to honour the Paris commitment despite his criticisms of the deal as bad for US workers and his description of climate change as a hoax.

That list includes the Pope, who gave Mr Trump a copy of his 2015 encyclical on climate change following a half-hour meeting in his private study on Wednesday.

Italian Prime Minister Paolo Gentiloni raised the pact in his meeting with Mr Trump, and newly elected French President Emmanuel Ma- cron was set to press the issue in his first face-to-face meeting with the US President.

At home, Democrats say honouring the pact among about 200 nations is important for US strategic interests. Senator Ben Cardin said: "Our allies know how important US leadership is for there to be acceptable world action."

Mr Trump was in Brussels on Wednesday for a Nato meeting and returns to Italy today for talks with Group of Seven (G-7) leaders in Taormina, Sicily. The world's developed nations are hoping for a signal from him about the fate of the Paris pact during the G-7 summit, said German Environment Minister Barbara Hendricks.

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