March 14 (UPI) -- British Prime Minister Theresa May expelled 23 Russian diplomats on Wednesday over a recent nerve agent attack on a former Russian double agent.
Sergei Skripal, a 66-year-old former colonel in Russia's military intelligence service, and his 33-year-old daughter, Yulia Skripal, were found dead slumped on a bench in a British shopping district in Salisbury earlier this month.
The Russia-made poison, part of a group of nerve agents known as Novichok, made it "highly likely" that Moscow was behind the attack, May said earlier this week.
On Wednesday, May announced a sweeping response to what she called a "direct act by the Russian state," saying Britain would give the 23 "undeclared intelligence officers" just one week to leave -- marking the single largest expulsion in more than 30 years.
The prime minister said Britain would also consider new laws to combat spying and impose sanctions in response to the attack, adding that Britain would freeze Russian assets if evidence shows they may be used to threaten life or property.
"We will urgently develop proposals for new legislative powers to harden our defenses against all forms of hostile state activity," May told British lawmakers Wednesday. "We will also table a government amendment to the sanctions bill to strengthen our powers to impose sanctions in response to the violation of human rights."
May further announced the suspension of all planned bilateral contact between Britain and Russia -- including a visit by Moscow Foreign Minister Sergey Lavrov and attendance by British ministers or members of the royal family to the quadrennial FIFA World Cup, which will be held in Russia this summer.
"This was not just an act of attempted murder in Salisbury -- nor just an act against U.K.," May said. "It is an affront to the prohibition on the use of chemical weapons."
May said it's "tragic" the way Russian President Vladimir Putin has acted and noted that Britain "will not tolerate the threat to life of British people and others on British soil from the Russian government. Nor such a flagrant breach of Russia's international obligations."
Lavrov said Wednesday that Moscow had no motives for poisoning the Skripals.
"Yesterday, both our and foreign mass media mentioned quite a few arguments explaining why Russia could not have any such motives," Lavrov said. "Such motives might certainly exist in the minds of those who would like to push ahead with the Russophobic campaign in all spheres of human activity without an exception."
Lavrov said under the Chemical Weapons Convention, Britain is obliged to send an official request to the country it has suspicions about.
"But no such request was sent," Lavrov said.