Russia says US threats on Iran nuclear sites 'illegal and unacceptable'

Moscow has rejected as illegal US threats against Iran's nuclear infrastructure, the Russian foreign ministry said on Wednesday, as tensions between Washington and Tehran have ramped up in recent weeks.

The remarks follow a discussion between the deputy foreign ministers of Russia and Iran Sergei Ryabkov and Iranian deputy foreign minister Majid Takht Ravanchi on Wednesday in which the two sides accused Western countries of "artificially and unreasonably" inflaming tensions over Tehran's nuclear program.

Using military force against Iran and threatening to strike its nuclear infrastructure would be "illegal and unacceptable," the Russian foreign ministry said according to Reuters, as they would cause "large-scale and irreversible radiological and humanitarian consequences" for the Middle East and the world.

US president Donald Trump has repeatedly expressed his preference for a nuclear deal with Iran but warned that a failure to reach one within a timeframe he has set could lead to military action.

The exact start date of Trump's reported two-month deadline to Iran remains unclear.

Tehran has rejected direct negotiations with the Trump administration and has suggested indirect talks via Oman.

A day earlier, Ryabkov warned against a US strike on Iran and expressed optimism that the stand-off could be resolved diplomatically.

"There is still time, and the 'train has not left the station' yet. We must intensify efforts to reach a reasonable agreement," Ryabkov said in an interview with Russian journal International Affairs.

"Russia is ready to offer its services to Washington, Tehran and all parties interested in resolving this issue," he added.

Kremlin spokesman Dmitry Peskov also said last month that Russian President Vladimir Putin had agreed to mediate nuclear talks between Washington and Tehran.