Officials say CIA information helped thwart a terror attack in Russia

The United States provided intelligence to Russia that helped thwart a potentially deadly bomb attack in St Petersburg, US and Russian officials said on Sunday, in a rare public show of co-operation despite deep strains between the two countries.

Russian President Vladimir Putin telephoned US President Donald Trump on Sunday to thank him for the tip-off that the Kremlin said helped prevent a militant bomb attack on a cathedral in the Russian city, as well as other sites.

The White House did not disclose details about the plot itself, but said the attack "could have killed large numbers of people." Neither the Kremlin nor the White House identified the would-be attackers.

The US warning allowed Russian law enforcement agencies to arrest the suspects before they could carry out their plans, the White House and Kremlin said.

The phone call on Sunday between Trump and Putin was at least the second such call in the past week. On Thursday, Putin and Trump discussed the crisis in North Korea.

Cathedral threat 

The foiled attack was to have been carried out on Kazansky Cathedral, in Russia's second city of St Petersburg, and on other locations in the city where large numbers of people gather, the Kremlin statement said. The cathedral is a popular tourist site.

The White House seized on the foiled plot in St Petersburg as a sign of what Moscow and Washington could do if they co-operate.

"Both leaders agreed that this serves as an example of the positive things that can occur when our countries work together," the White House said, adding Trump appreciated the call from Putin.

Russian media reported last week that the Federal Security Service had detained followers of Daesh who had been planning a suicide bomb attack on Kazansky Cathedral on Saturday.

Putin said Russia would alert US authorities if it received information about any attack being planned on the US, the Kremlin said.

Russia has repeatedly been the target of attacks by militant groups, including an attack in April that killed 14 people when an explosion tore through a train carriage in a metro tunnel in St Petersburg.

Russian police detained several suspects in that attack from mainly Muslim states in ex-Soviet central Asia.