The body of the pontiff, who died on Monday, has been moved into the church for a period of public mourning.
The tech boss says he intends to spend only one to two days a week on Trump administration matters.
His comments come amid a trade war with Beijing, and after his attacks on the US central bank's boss.
US Secretary of State Marco Rubio and special envoy Steve Witkoff are no longer attending the talks.
Several names are in the fray as cardinals prepare to gather in the Vatican to elect Pope Francis' successor.
Trump also expressed optimism that trade relations with China can be improved and a deal can be reached.
Mandatory evacuation orders were issued and major highways in the path of the fire shut down as it spread.
The move is part of the government's plan to combat increasing migration from neighbouring Haiti
The move is part of the government's plan to combat increasing migration from neighbouring Haiti
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