Thailand's ousted ex-prime ministers, Yingluck Shinawatra and her brother, Thaksin Shinawatra, both fugitives forced to live overseas, left Japan for Hong Kong on Tuesday, sources close to them said.

They had stayed in Japan since Saturday, according to the sources.

Yingluck was last year sentenced in absentia by Thailand's Supreme Court to five years in prison for negligence in handling a rice subsidy project that resulted in massive losses to state coffers. She fled the country last August ahead of the verdict and was later confirmed to be in Britain.

Thaksin was ousted as prime minister in a military coup in 2006. He fled abroad to avoid a corruption conviction.

Yingluck, who is believed to have visited Japan for the first time after fleeing Thailand, was accompanied by Thaksin as well as Somchai Wongsawat, their brother-in-law and another former Thai prime minister. They stayed in Japan for private purposes, the sources said.

Yingluck was granted permission for entry by the Japanese government, the sources said. She has sought asylum in Britain.