The White House is considering cancelling a summit between Barack Obama and Russian President Vladimir Putin in Moscow, a move that would further aggravate the already tense relationship between the two leaders.
The White House is dangling that option over the Russians as Moscow considers a temporary asylum petition from Edward Snowden, who is accused of leaking information about classified US intelligence programmes.
But officials have privately signalled that scrapping the talks would also be retaliation for other areas of disagreement with Russia, including its continued support for Syrian President Bashar Assad's attacks against civilians.
Regardless of what happens with Snowden, the White House says Obama will still attend an international summit in St Petersburg. But officials have gone out of their way in recent days to avoid publicly committing to the meetings in Moscow.
"The president intends to travel to Russia for the G20 Summit," White House spokesman Jay Carney said. "And I have no further announcements to make beyond what we've said in the past about the president's travel to Russia in the fall."
By simply considering cancelling the trip, the Obama administration is indicating its concern that the Kremlin will allow Snowden to take refuge in Russia. The White House has called on Russia to return the 30-year-old former government contractor to the US to face espionage charges.
Snowden, in a temporary asylum request submitted by his lawyer on Tuesday, claimed he faces persecution from the US government and could face torture or death.
Putin's spokesman said yesterday that Kremlin has no knowledge of Snowden seeking Russian citizenship.
"Citizenship? This is the first I've heard of it. It's news to me," Putin spokesman Dmitry Peskov told reporters.
Andrew Kuchins, of the Centre for Strategic and International Studies, said the White House's cancellation threat could be effective leverage over Putin, who will want to avoid an embarrassment on the world stage.
"When the spotlight of the world is on him and Russia, he doesn't want that to reveal a lot of negative things which are going to be distractions," Kuchins said. Cancelling the US-Russia talks would deepen the tensions between the two leaders, probably making it even more difficult for the countries to find common ground on areas of disagreement.
Russia was accused by the US of providing military support to Assad that has allowed him to cling to power during more than two years of clashes with rebels seeking to overthrow him.
The US deeply angered Russia this year when it announced sanctions against 18 Russians as part of a law named after Sergei Magnitsky, a Russian lawyer who was arrested in 2008 for tax evasion after accusing Russian police officials of stealing US$230 million in tax rebates. Within days of the Treasury Department announcement, Russia announced that it was banning US adoptions of Russian children.
On Thursday, the White House also said it was "deeply disappointed and concerned" by the conviction of opposition leader Alexei Navalny.
Kuchins said that while granting Snowden asylum would certainly be the impetus for cancelling Obama's Moscow trip, it would not be the only reason.
"It would be saying at least two things to the Russians," Kuchins said. "That granting asylum to Edward Snowden was a bridge too far, and that we don't feel like we're actually losing so much out of the cancellation of the summit because we didn't expect to get much out of it."