(File image) United States President Barack Obama

New York - President Barack Obama will skip an Asia-Pacific summit in Russia hosted by President Vladimir Putin in early September, the White House said on Monday.

The White House made official what had been widely assumed, since the APEC gathering will take place the same week as the Democratic national convention in North Carolina, where Obama will accept his party's nomination for re-election on September 6.

Both countries have denied using summit decisions to snub the other.

The White House announcement followed Putin's decision, after his return to the Kremlin last week, to pull out of a summit of the Group of Eight major industrialised nations to be hosted this weekend by Obama at the Camp David presidential retreat.

US officials had long signaled that a presidential trip to Vladivostok was unlikely so close to the November election, and one Obama aide had dismissed the notion it was retaliation for Putin's cancellation.

Russia's senior official for APEC, Gennady Ovechko, told reporters in Washington on Monday that Moscow had heard a year ago that Obama might not be able to attend the Vladivostok meeting because of the US political calendar.

“In May 2011, there were some approaches from the United States government on this issue. And again, it's easy to understand. We were quite sympathetic,” Ovechko said after a talk at the Centre for Strategic and International Studies, a US think tank, on Russia's goals for APEC this year.

“We (would) be very happy if the US president could visit Vladivostok for the summit, though we admit there could be some important domestic circumstances that could prevent him from coming,” Ovechko said.

The two leaders have agreed to reschedule their meeting, the first since a rocky encounter in 2009 at Putin's dacha outside Moscow, to the sidelines of a G20 summit in Mexico in June.

Moscow has denied that Putin's decision to skip the G8 and instead send his junior partner, Prime Minister Dmitry Medvedev, was intended as a slight to Obama. They insist Putin was staying home to fill posts in his new cabinet.

But some Kremlin watchers see it as message from Putin that as long as he is in charge, Russia will not bend to Washington's will. The “reset” in relations that Obama has pursued is threatened by disputes over missile defence and Syria.

Some US policy makers believe that a key reason that Putin is staying away is to avoid looking weakened on the world stage while he re-asserts himself in the face of recent protests at home.

Putin's absence could also spare Obama, who had planned Oval Office talks with him, from having to fend off new Republican accusations of being too soft on a former Cold War foe.

A trip to Russia just two months before the election would have cut into Obama's time to devote to his hard-fought run for a second term.

Obama's press secretary, Jay Carney, confirmed the president's decision not to attend the Asia-Pacific Economic Co-operation summit during a visit to New York. - Reuters