(AP) — Rubio said Wednesday that China needs to be part of any future talks to impose limits on nuclear weapons, noting the country’s “vast and rapidly growing stockpile.”

The last remaining nuclear arms pact between Russia and the United States is set to expire Thursday. Russian President Vladimir Putin has declared readiness to stick to the treaty’s limits for another year if Washington follows suit, while Rubio reiterated President Trump’s stance that China needs to be involved in such discussions.

Trump said Wednesday that he spoke with President Xi Jinping of China, including on subjects involving the military. But Trump didn’t elaborate on whether those talks involved their countries’ nuclear arsenals.