President Donald Trump will meet jointly next week with China’s leader Xi Jinping and Russian President Vladimir Putin, the White House said Friday, a first-ever trilateral sit-down between the leaders of the three countries.

The meeting, on the sidelines of the APEC summit in China, will focus on nuclear non-proliferation, a topic Trump has said he believes could yield a new agreement between the world’s biggest nuclear-armed states.

“The President has made it clear that, among other topics, he will discuss the reduction of nuclear weapons in the world. This proliferation, President Trump believes, is very dangerous,” Olivia Wales, a White House spokesman, told reporters.

The last nuclear arms treaty between the US and Russia expired in February.

China, meanwhile, has been rapidly building its nuclear arsenal.

Officials downplayed the prospect of striking a new deal on nuclear matters, suggesting instead the talks would be a starting point.

“We do not expect to get to any kind of agreement,” a senior US official said. “I would characterize this as the entry point, the first conversation, certainly at the leader level, between these countries.”

“So this is the beginning of hopefully a conversation that can be productive going forward,” the official went on.

Officials said the world leaders also planned to discuss Iran.

A senior US official said Elon Musk is expected to go on the trip with Trump, among others, though he is not expected to attend the trilateral meeting.

Beijing and Moscow have yet to officially confirm participation in the trilateral summit. (CNN)

PHOTO:Russian President Vladimir Putin and Chinese leader Xi Jinping attend a welcoming ceremony at the Great Hall of the People in Beijing, on May 20.