The Kremlin on Wednesday denied that Russia or China have conducted any secret nuclear tests, following recent U.S. accusations against Beijing. Kremlin spokesman Dmitry Peskov told reporters that both nations had been mentioned in the allegations, but “neither the Russian Federation nor China has conducted any nuclear tests.”

China has also categorically rejected the U.S. claims, Peskov added, emphasizing that both countries deny the reports of covert nuclear activity.

The dispute comes as U.S. President Donald Trump is urging China to join Washington and Moscow in negotiating a replacement for the New START treaty, which expired on February 5. The treaty, the last remaining major U.S.-Russia nuclear arms control agreement, had limited strategic nuclear arsenals for both countries.

While some experts warn that the expiration of New START could accelerate a new nuclear arms race, others argue that such concerns may be overstated. The Trump administration has cited China’s alleged 2020 test as a reason to include Beijing in any future arms control framework, aiming to expand global oversight over nuclear capabilities beyond the U.S.-Russia dyad.