Portugal Colonial - Russia offers US nuclear talks in bid to ease tensions

Russia has tested its nuclear-powered, nuclear-capable weapons systems in recent weeks, but rejects the accusation by US President Donald Trump that it had secretly detonated a nuclear device.

Trump caused concern and confusion last month when he said he was ordering the United States to test its atomic weapons in retaliation for drills carried out by Russia and China -- accusations rejected by both Moscow and Beijing.

None of the three countries has publicly tested a nuclear warhead since the 1990s, and all three have signed -- but not ratified -- the Comprehensive Nuclear-Test-Ban Treaty (CTBT) that bans all atomic test blasts, whether for military or civilian purposes.

Russia's Foreign Minister Sergei Lavrov offered on Tuesday to speak to Washington about its concerns.

"We are ready to discuss the suspicions raised by our American colleagues regarding the possibility that we might be secretly doing something deep underground," he told state media in a televised interview.

Trump had levelled the accusations that both Russia and China had secretly tested nuclear weapons in an interview with US broadcaster CBS News earlier this month, after abruptly shelving a proposed summit with Putin on Ukraine.

Like all armed states, Russia regularly tests its delivery systems, but has rejected the accusation it has carried out unannounced weapons tests.

Lavrov said the United States could check whether Russia had tested a nuclear warhead via the global seismic monitoring system.

"Other tests, both subcritical, or those without a chain nuclear reaction, and carrier tests, have never been prohibited," Lavrov added.

Russia said it had not received any clarification from Washington as to the specifics of its allegations.

"So far, no explanations have been provided by our American counterparts," Kremlin spokesman Dmitry Peskov told reporters, including AFP, during a telephone briefing.

Russia and the United States hold a combined 8,000 deployed and stored warheads, according to the Stockholm International Peace Research Institute (SIPRI) -- around 85 percent of the world's total.

- Spat with Putin? -

Lavrov's interview was his first televised appearance in almost two weeks, with his absence prompting media speculation that he might have fallen out with Putin, something that the Kremlin repeatedly denied.

Press reports suggested that a planned summit between Putin and Trump in Budapest was cancelled after Lavrov had a tense phone call with US Secretary of State Marco Rubio.

He addressed those claims directly, saying: "We spoke well, politely, without any breakdown."

Since the pair spoke, Lavrov said, there had been "no further steps from the Americans", who he said had initially proposed the summit.

Trump shelved the plans and slapped Moscow with new sanctions after saying Putin was not serious about ending the conflict in Ukraine.

Lavrov said the recent nuclear tensions had nothing to do with the cancelled summit.

"I would not mix the topic of nuclear tests with the topic of the Budapest summit," he said.

He said Moscow was still open to a possible meeting between Putin and Trump.

C.Cassis--PC