WASHINGTON (AFP) - Strategic and tough sanctions against Moscow have effectively battled Russian President Vladimir Putin's aggression in Ukraine, US President Barack Obama said in an interview broadcast on Monday.
Mr Obama recalled how Mr Putin had convinced many in Washington that the Russian leader "was a genius" for his lightning-quick annexation of the Crimean peninsula and invasion of areas of eastern Ukraine.
But the US administration's non-aggressive response, while frustrating hawkish Republicans in Congress who advocated more forceful intervention, paid dividends in the long run, with sanctions now biting into the limping Russian economy.
Mr Putin believed "he had outmanoeuvred all of us and he had bullied and strategised his way into expanding Russian power", Mr Obama told National Public Radio in a Dec 19 interview before flying to Hawaii for Christmas vacation.
"I said at the time we don't want war with Russia, but we can apply steady (sanctions) pressure working with our European partners," Obama said.
"And today, I'd sense that at least outside of Russia, maybe some people are thinking what Putin did wasn't so smart.
"Part of our rationale in this process was that the only thing keeping that economy afloat was the price of oil," Mr Obama said.
Steady sanctions pressure "would make the economy of Russia sufficiently vulnerable that if and when there were (oil price) disruptions... that they'd have enormous difficulty managing it".
Economic indicators show Russia is sliding towards recession, a sharp reversal of fortune for Mr Putin, who is contending with the first shrinkage in his nation's economy since 2009.
The rouble has slumped by 40 per cent this year, mostly due to crude oil prices falling by half in the past six months.
Since the Crimea annexation, the United States and European Union have slapped multiple levels of economic sanctions on Russia.