Moscow is asking Washington to clarify Donald Trump‘s recent statements about a possible resumption of nuclear tests, on the understanding that doing so would mean serious reactions from other countries.

Russian Foreign Ministry spokeswoman Maria Zakharova made the relevant statements at a briefing for journalists.

Trump said last week that he had ordered the US armed forces to immediately proceed with nuclear weapons testing after 33 years. But no one has since clarified whether the US president was talking about resuming nuclear tests, testing nuclear-capable missiles or anything else.

Given this lack of clarity, Russian President Vladimir Putin has ordered plans to prepare plans for a nuclear test in response to any U.S. nuclear test.

No nuclear power has conducted a nuclear test in three decades – with the exception of North Korea (six times between 2006 and 2017). Russia has stopped nuclear testing since 1990, the US since 1992 and China since 1996.