The move marks a stark low point in US-Russian relations and raised questions about the "reset" in ties that Obama embarked on in his first term to try to gain more diplomatic cooperation, only to find that deep differences remained.

"Following a careful review begun in July, we have reached the conclusion that there is not enough recent progress in our bilateral agenda with Russia to hold a US-Russia summit in early September," White House spokesman Jay Carney said in a statement.

The Russian government expressed disappointment at the decision, which means Obama will skip Moscow talks with Putin but still attend a G20 summit in St. Petersburg Sept. 5-6. Obama will stop in Sweden on Sept. 4 instead of visiting Moscow.

"It is clear that the decision is due to the situation around the former U.S. special services employee Snowden, which we did not create," Putin's foreign policy aide, Yuri Ushakov, told reporters in Moscow.

He said Russia's invitation for Obama to visit Russia still stood.

Beyond Snowden, however, a long list of grievances separate the two governments, topped by Russia's support for Syrian President Bashar al-Assad in Syria's civil war.

"The real issue here is that the US-Russian relationship has been adrift since 2011," said Andrew Weiss, a Russian expert at the Carnegie Endowment for International Peace. "Snowden is the obvious sore point and source of great public attention. But the relationship has been sagging and unmoored for some time now."

Obama and White House officials had debated whether to go ahead with the Moscow visit to give Obama the opportunity to outline his concerns to Putin face-to-face, but decided instead to express US displeasure publicly by canceling the summit altogether. A June meeting between the two leaders on the fringes of a G8 summit in Northern Ireland was testy.

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