DHAKA: USA president Barack Obama has said Vladimir Putin made a ‘strategic mistake’ when he annexed Crimea, in a move that was ‘not so smart’.

Those thinking his Russian counterpart was a ‘genius’ had been proven wrong by Russia's economic crisis, he said, reports the BBC.

International sanctions had made Russia’s economy particularly vulnerable to changes in oil price, Obama said.

He also refused to rule out opening a US embassy in Iran soon.

‘I never say never but I think these things have to go in steps’ he told NPR’s Steve Inskeep in the Oval Office.

Obama was giving a wide-ranging interview with NPR shortly before leaving for Hawaii for his annual holiday.

He criticised his political opponents who claimed he had been outdone by Russia’s president.

‘You’ll recall that three or four months ago, everybody in Washington was convinced that president Putin was a genius and he had outmanoeuvred all of us and he had bullied and strategised his way into expanding Russian power,’ he said.

‘Today, I’d sense that at least outside of Russia, maybe some people are thinking what Putin did wasn’t so smart.’

BDST: 1550 HRS, DEC 30, 2014