By The Canadian Press

OTTAWA - An international human-rights lawyer is quietly trying to enlist Canadian political and diplomatic clout in support of causes ranging from a jailed Russian billionaire to a Singapore politician.

Robert Amsterdam is lobbying cabinet ministers, MPs and senators in his quest for help. The Ottawa-born lawyer, who is now based in London, is known for fighting state-sponsored injustice.

He represents Mikhail Khodorkovsky, a Russian oil tycoon jailed on fraud charges which Amsterdam says were trumped up for political reasons.

He defends Chee Soon Juan, a Singapore opposition politician who has been saddled with enormous defamation damages in government law suits.

Amsterdam also pillories the Venezuelan government of Hugo Chavez, which he says has hounded the opposition out of the country.

"We're looking to find ways that the government of Canada . . . will make its voice heard in respect to what is going on in Russia, Venezuela and Singapore when it comes to the situation regarding rule of law," he said Wednesday.

Chavez is running "essentially a leftist military junta" which has made common cause with international pariahs such as Iran, he said.

Singapore has a government "that sees all opposition as somehow a danger to the regime . . . and fails to afford basic human-rights protection to political opponents."