Russia's Deputy Foreign Minister Sergei Ryabkov attends the St. Petersburg International Economic Forum (SPIEF) in Saint Petersburg, Russia June 18, 2025. REUTERS/Anton Vaganov

MOSCOW (Reuters) -A top Russian diplomat said on Wednesday that Russia would swiftly carry out a nuclear test if the United States did so, noting that the U.S. had been working to get its testing infrastructure ready, the state RIA news agency reported.

President Vladimir Putin said in October that Russia would carry out a nuclear test if another nuclear power did so after saying that Moscow had seen signs that an unnamed country was preparing to conduct such tests.

RIA cited Deputy Foreign Minister Sergei Ryabkov as saying that Russia had observed that the U.S. had been working for some time to get its own testing infrastructure ready.

If the U.S. did carry out a test, it cited Ryabkov as saying Moscow would quickly follow suit.

(Reporting by Reuters; Writing by Anastasia TeterevlevaEditing by Andrew Osborn)