US federal agents inspected a Russian trade mission in Washington to confirm its closure on Saturday, despite a furious diplomatic protest from Moscow.

The United States and Russia are in the grip of a diplomatic dispute, and the trade representative's office is part of a group of properties Washington has ordered closed.

Russian officials were forewarned of the inspection and, according to a report in Foreign Policy magazine, lit a fire on Friday apparently to burn documents at the facility.

"Today, Russian Embassy personnel, together with State Department officials, walked through three properties in San Francisco, New York and Washington, DC that the Russian government is required to close," a State Department official said.

"These inspections were carried out to secure and protect the facilities and to confirm the Russian government had vacated the premises," he said, adding that all three are now closed.

On Saturday, US agents could be seen on the grounds of the Washington mansion, which served as both the home and office of the Russian trade representative. It has been owned by Moscow since the Soviet era.

The US State Department official said Washington had fully complied with its duties under the Vienna Convention in preserving the security of foreign missions, but in Moscow the Russian foreign ministry was furious even before the inspection began.

The ministry summoned acting US mission head Anthony Godfrey and gave him a "note of protest over the intention of the American authorities to conduct a search."

Russian news agency RIA-Novosti reported that the search began in the presence of Russian officials.

But the ministry nevertheless warned that the visit "could be used by the US intelligence services to organize an anti-Russian provocation involving planting compromising materials."

The trade mission in Washington is one of three diplomatic buildings -- including the consulate in San Francisco and an office in New York -- that the US had ordered Moscow to vacate by Saturday.

Russia's foreign ministry said Friday that US intelligence was also planning to search the consulate in San Francisco.

Black smoke was seen rising from a chimney at the consulate on Friday, and firefighters confirmed its occupants were burning unidentified objects.

A spokeswoman for the Russian foreign ministry insisted the smoke was due to measures to "preserve the building" at a time when officials were gearing up to leave.

- Diplomatic saga -

Washington issued the closure order Thursday in retaliation for Moscow ordering the US to slash its diplomatic mission by 755 personnel by September 1.

The number of US diplomatic staff will now be capped at 455, the same number that Russia has in the United States.

The recent surge in tensions between the two nuclear-armed powers was an early diplomatic setback for US President Donald Trump.

During his campaign for office last year and in the early days of his presidency he had promised to try to improve relations with Russian President Vladimir Putin.

Ties had slumped to their lowest point since the Cold War after the Kremlin's seizure of Crimea from Ukraine in 2014.

The West slapped sanctions on Russia over its meddling in its ex-Soviet neighbor, sparking a revenge embargo from Moscow against agricultural products.

Last year, tensions again escalated after US intelligence accused Putin of masterminding a hacking and influence campaign to tip the presidential vote to Trump.

And in the waning days of his tenure, president Barack Obama punished Russia by turfing out 35 diplomats and closing diplomatic compounds in New York and Maryland.

Moscow initially held off from retaliating but when Congress passed new sanctions, the Kremlin decided to belatedly strike back and ordered the US staff cut.

Congress worded the sanctions bill to make it impossible for Trump to waive them without consulting lawmakers -- a move which further infuriated Moscow.

"First, it ends hopes for improving our relations with the new US administration," Russia's Prime Minister Dmitri Medvedev wrote on Facebook.

"Second, it is a declaration of a full-fledged economic war on Russia. Third, the Trump administration has shown its total weakness by handing over executive power to Congress in the most humiliating way."

Russia's Foreign Minister Sergei Lavrov said on Thursday that Moscow was studying the latest US order to shutter the compounds and would then decide how to react.

In a related development, the US Justice Department, in a court filing Friday, has confirmed there is no evidence to back up Trump's claim that Obama wiretapped Trump Tower during the 2016 election.

source: AFP