WASHINGTON — The Trump administration said Wednesday it would impose more sanctions against Russia as punishment for its use of a nerve agent in an attempt in March to assassinate British citizen and ex-Russian intelligence officer Sergei Skripal and his daughter.
A terse release from the State Department said that the United States had determined Russian responsibility for the attack in Salisbury, England — a British conclusion the administration had already accepted — under a 1991 US law on biological and chemical weapons use that requires the president to impose sanctions.
Russia has denied responsibility for the attack.
A State Department official said the sanctions could have a significant impact on trade with Russia, including prohibition of licenses on sending some US goods there, such as electronic devices. But unless Russia agrees within 90 days to stop all use of chemical weapons and permit inspections to confirm their elimination, additionally mandated measures could cut off almost all trade between the two countries, prohibit landing rights for Russian airlines, and lead to a suspension of diplomatic relations.
The 1991 Chemical and Biological Weapons Control and Warfare Elimination Act ‘‘requires the president to make a determination with respect to whether a country has used chemical or biological weapons in violation of international law or has used lethal chemical or biological weapons against its own nationals,’’ the State Department said. Once that determination is made, sanctions are mandated, unless the president determines it is in the national-security interest of the United States to waive them.
In March, two weeks after the Skripal attack, President Trump signed a statement, together with the leaders of France, Germany, and Britain, blaming Russia for the assassination attempt on the former Russian military officer, who was convicted of spying for Britain. Skripal settled in Britain after a 2010 prisoner exchange.
The statement demanded that Russia ‘‘address all questions’’ related to the attack and provide ‘‘full and complete disclosure’’ of its Novichok chemical program.
Trump also ordered the expulsion of 60 Russians, including 12 identified as intelligence officers, and closed the Russian consulate in Seattle. The move was part of a wave of similar actions taken by Western countries in solidarity with Britain.
Last month, British Prime Minister Theresa May urged Trump to raise the issue of the poisonings when he met with Russian President Vladimir Putin in Helsinki, although it remained unclear whether the subject came up in their talks.
The Organization for the Prohibition of Chemical Weapons, the international chemical weapons watchdog, concluded in April that the nerve agent Novichok, known to have been first produced by the Soviet military, had been used in the attack against the Skripals, both of whom survived, although it did not assign blame.
Republican Representative Edward Royce of California, chairman of the House Foreign Affairs Committee, in a letter sent to Trump shortly after the Skripal attack, said he was encouraged by the joint statement Trump signed with allies. But he also reminded the administration of the 1991 legislation and asked for an official determination of whether Russia had violated it.
The United States, Royce noted, had imposed sanctions against North Korea in response to what it determined was a violation of the law following the assassination of Kim Jong Un’s brother with the chemical warfare agent VX as he was passing through the international airport in Kuala Lumpur, Malaysia, in February 2017.
In June, two British citizens living near Salisbury, where the Skripals were poisoned, also came in contact with Novichok. One of them, Charlie Rowley, said that he believed the poison came from a bottle of what he thought to be perfume that he found on the ground and gave to his girlfriend, Dawn Sturgess. Both quickly sickened with what the British government said was Novichok, although it had not yet determined whether the poison was the same batch as that administered to the Skripals.
Sturgess, 44, died a week after the exposure.