By ANGELA CHARLTON
Associated Press

MOSCOW (AP) - Moscow is awaiting nearly two dozen Russian diplomats ordered to leave Britain following a nerve agent attack on U.K. soil.

The Russian Foreign Ministry told The Associated Press that the 23 diplomats are expected to leave British territory Tuesday.

Several dozen people, including children, emerged from Russia's west London embassy on Tuesday morning, carrying suitcases, bags and pet carriers. Some hugged before they boarded vehicles including a white minibus and were driven away.

On Wednesday Prime Minister Theresa May gave the diplomats - whom she said were undeclared intelligence agents - a week to leave Britain, an order which prompted Russia to retaliate with its own expulsion of 23 British diplomats. The British diplomats are expected to leave Moscow in the coming days.

Tensions between the two countries have ratcheted higher since the March 4 poisoning of ex-Russian spy Sergei Skripal and his daughter Yulia in the English city of Salisbury. They remain in critical condition.

Britain says the pair were poisoned with a Soviet-developed form of nerve agent known as Novichok. Western powers see the attack as a sign of increasingly aggressive Russian meddling abroad.

Russia denies involvement. President Vladimir Putin's spokesman, Dmitry Peskov, insisted Tuesday that "Russia has no stocks of chemical weapons of any kind."

Asked why Russia isn't showing proof of its innocence, he said, "let's stay sober-minded and first of all wait for proof from Britain" that Russia was to blame.

Britain's National Security Council was meeting Tuesday to consider possible further measures against Russia. May and other European Union leaders are due to discuss the poisoning at a summit Thursday. The EU on Monday condemned the poisoning and called on Russia to "address urgently" British questions over the Novichok nerve agent program.

The Russian Foreign Ministry called Britain's accusations "speculative and baseless."

In a statement, it accused Britain and other EU member states of continuing development of similar nerve agents and said Britain's government is stirring up "media hysteria" around the case to distract Britons from the government's troubles in negotiating the country's exit from the EU.

Russia insists it gave up all its chemical weapons under international oversight.

The British military and police are continuing to search for clues around Salisbury into what happened. International chemical weapons experts are due to take samples of the nerve agent used, which Britain says is the Soviet-developed Novichok.

British police investigators say it may take months to complete the widening inquiry. The focus is on the movement of the Skripals in the hours before they were found unconscious on a bench in the cathedral city 90 miles (145 kms) southwest of London. A police officer who came to their assistance is in serious condition.

"This is going to be frustrating for people," said Neil Basu, head of counterterrorism at the Metropolitan Police "It is going to take weeks, possibly months to do this."

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Jill Lawless in London contributed to this story.

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