Speculation rife over why Vladimir Putin canceled G8 summit appearance at Camp David

Numerous theories as to why Vladimir Putin canceled an appearance at the Group of Eight (G8) summit at Camp David next week include that he is facing unfamiliar challenges at home, according to the Washington Post.

The paper cites sources as saying that Putin has had to rethink his cabinet because of continuing protests.

Among the other "theories" are that he is resorting to anti-Americanism as a time of stress on his leadership, that he is avoiding the international stage at a moment when he appears off-balance; and that he is postponing until after visiting more loyal allies.

Agence France-Presse reported that Putin would make what could be his first foreign trip to China next month.

Citing Russian news agencies, AFP wrote that Putin's June 5-7 visit would include talks with Chinese President Hu Jintao and attendance at the Shanghai Cooperation Organisation summit. 

Putin, AFP wrote, has sought to develop relations with China, paying three formal visits there as president between 2000 and 2008.

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The Associated Press cited officials from Russia and the US as insisting Putin's decision to skip the high-profile economic gathering was not a snub to President Barack Obama.

However, the news service wrote, the decision not to attend a much-anticipated Oval Office meeting with Obama may set a sour tone for the next four years, provided Obama wins re-election.

Also, the AP wrote, Putin has signaled that he will hold off on any major new cooperation with the US until he knows which president he will be dealing with.

Mitt Romney, the likely Republican challenger, has called Russia an "enemy."

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