Trump to sign Russia sanctions, Moscow retaliates

US President Donald Trump will sign legislation that imposes sanctions on Russia, the White House said on Friday, after Moscow ordered the United States to cut hundreds of diplomatic staff in retaliation for the measures and said it was seizing two US diplomatic properties.

Moscow's decision, which had echoes of the Cold War, was announced by the Foreign Ministry on Friday, a day after the US Senate overwhelmingly approved new sanctions on Russia.

The legislation was in part a response to conclusions by US intelligence agencies that Russia meddled in the 2016 US presidential election, and to further punish Russia for its annexation of Crimea in 2014.

Late on Friday, the White House issued a statement saying Trump would sign the bill after reviewing the final version. The statement made no reference to Russia's retaliatory measures.

Russia's response, announced by the Foreign Ministry, came a day after the US Senate voted to slap new sanctions on Russia, putting President Donald Trump in a tough position by forcing him to take a hard line on Moscow or veto the legislation and anger his own Republican Party.

Earlier on Wednesday, President Vladimir Putin warned that Russia had so far exercised restraint, but would have to retaliate against what he described as boorish and unreasonable US behaviour.

Relations between the two countries, already at a post-Cold War low, have deteriorated even further after US intelligence agencies accused Russia of trying to meddle in last year's US presidential election, something Moscow flatly denies.

The Russian Foreign Ministry said on Friday that the US had time until September,1 to reduce its diplomatic staff in Russia to 455 people, the same number of Russian diplomats it said were left in the US after Washington expelled 35 Russians in December.

It said in a statement that the decision by Congress to impose new sanctions confirmed "the extreme aggression of the United States in international affairs."

It was not immediately clear how many US diplomats and other workers would be forced to leave the country.

An official at the US embassy in Moscow, who declined to be named, said there were around 1,100 US diplomatic staff in Russia. That included Russian citizens and US citizens.

Most staff, including around 300 US citizens, work in the main embassy in Moscow with others based in outlying consulates.

The Russian Foreign Ministry said it was also seizing a Moscow dacha compound used by US diplomats to relax from August 1, as well as a US diplomatic warehouse in Moscow.

The outgoing Obama administration seized two Russian diplomatic compounds, one in New York and another in Maryland, at the same time as it expelled the Russian diplomats in December.

The Russian Foreign Ministry warned it would respond in kind if Washington decided to expel any Russian diplomats.