A spat over the cold war on Friday between President Barack Obama of the US and Vladimir Putin, the Russian prime minister, raised tensions before next week’s US-Russia summit.

In a television interview before his meetings with Mr Putin and President Dmitry Medvedev, Mr Obama said: “It’s important that even as we move forward with President Med­ved­ev, Putin understands that the old cold-war app­roach to US-Russian relations is outdated, that it’s time to move forward in a different direction.