Palin is due to deliver a keynote speech at the India Today Conclave in New Delhi on Saturday evening. Organisers of the event were unable to provide details of her itinerary but confirmed she had begun her visit to the country.

The former Alaska governor has said she will travel from Delhi to Israel to meet Prime Minister Benjamin Netanyahu, in what many observers in the US say is a tour designed to tackle accusations that she lacks international experience.

Palin, a conservative Republican who was John McCain's surprise pick as a running mate in the 2008 presidential race, will speak on "My Vision for America" at the conference in Delhi.

During the last election campaign, she famously said that Alaska's proximity to Russia gave her an understanding of world affairs.

Before being picked by McCain, she had only gone overseas to meet US soldiers serving in the Middle East.

Palin, 47, who has weakened in recent US opinion polls, says she has not yet decided whether to seek the Republican party nomination for the 2012 presidential election.

The US embassy in Delhi declined to comment on Palin's visit, saying she was travelling as a private citizen.

Other speakers at the Delhi conference include Egyptian presidential contender Mohamed ElBaradei and feminist writer Germaine Greer.