Russian President Vladimir Putin earlier this month rejected an offer from US President Barack Obama for landmark bilateral talks at the White House, the Kremlin revealed Tuesday.

Less than a week before Putin's 7 May inauguration, he received a missive from Obama touching upon bilateral and international issues and inviting him to discuss them in a bilateral summit on the sidelines of the May 18-19 G8 summit, Putin's foreign policy aide Yury Ushakov said.

"Obama sent his letter on 2 May," Ushakov told a briefing. "He even proposed holding a separate meeting at the White House in Washington outside of the framework of the G8."

But the Russian strongman told him he would not be able to travel to the United States and instead sent his protege and Kremlin predecessor Dmitry Medvedev to the summit at Obama's Camp David residence in Maryland.

The Kremlin said Putin could not go because he was too busy forming a government after his inauguration. Analysts say the Kremlin's explanation for the cancellation of the talks does not hold water.

After Putin's refusal to go the United States, the White House said Obama would not attend the APEC summit Russia hosts in Vladivostok in September, which comes soon after the Democratic presidential nomination convention.

Putin's trip to Washington would have made the United States his first foreign destination upon the Kremlin comeback.

Ushakov denied the cancellation of the US visit was meant as a snub, saying Putin was keen to pursue "stable" relations with Washington and stressed that the Russian President wrote Obama a long letter in return.

"It's a very substantial exchange," he said of the letters. "There are literally eight to nine pages there, both on our side and their side," he said.

Obama and Putin are now scheduled to meet on the sidelines of the G20 summit in Mexico next month.

"Vladimir Vladimirovich hopes for a most active development of stable, smooth, constructive relations with the American partners," Ushakov said. "It's important that the White House shares this attitude."