Alexander Petrov and Ruslan Boshirov, who were formally accused of attempting to murder former Russian intelligence officer Sergei Skripal and his daughter Yulia in Salisbury, are seen in an image handed out by the Metropolitan Police in London, Britain September 5, 2018. Metroplitan Police handout via REUTERS

LONDON (Reuters) - The United States stands with Britain in holding Russia accountable for its “act of aggression” on British soil, US Ambassador to Britain Woody Johnson said on Wednesday.

British prosecutors have charged two Russians for the attempted murder of a former Russian spy and his daughter with a nerve agent in Salisbury, naming suspects for the first time in a case that has caused one of the biggest East-West rifts in decades.

“The U.S. & UK stand firmly together in holding Russia accountable for its act of aggression on UK soil,” Johnson said on Twitter.