Russian agents have been blamed for the poisoning of Skripal and his daughter in the English city of Salisbury in March last year using the Soviet-developed nerve agent Novichok.

Washington said Saturday it will oppose "the extension of any loan or financial or technical assistance to Russia" by international financial institutions and put limits on US banks from financing Russian sovereign debt, US State Department spokeswoman Morgan Ortagus said in a statement.

The US will also limit the export of goods and technology to Russia, Ortagus added.

The Salisbury attack, the first offensive use of chemical weapons in Europe since World War II, caused an international outcry and prompted a mass expulsion of Russian diplomats by Western nations.

Moscow denies involvement in the poisoning and has offered numerous and varied alternative explanations and counter-accusations.

Skripal, a former officer with Russia's GRU military intelligence agency, was found guilty in 2006 of "high treason" before being traded in a spy exchange between Moscow, London and Washington.

In January the European Union imposed chemical weapons sanctions on nine Russian and Syrian officials, including the chief of the powerful GRU.