US actor Harrison Ford and other celebrities have joined conservationists in an effort to save the tiger - an animal experts say may become extinct within the next few decades.

Ford, the star of the latest "Indiana Jones" movie, has joined the World Bank's latest initiative which looks at various ways to protect wild tigers.

During the next six months, the Bank promises to hold "open and frank dialogues" with all stakeholders in tiger range countries - governments and non-governmental organizations - about which tiger conservation methods have worked in the past and which have not.

"By committing to help wild tigers, the World Bank is sounding its intention to be a global leader in biodiversity conservation," Ford told an event at Washington's Smithsonian National Zoo.

The Bank's announcement was welcomed by the 39 member organizations of the International Tiger Coalition (ITC).

"The potential loss of wild tigers is a global problem that requires a global solution," said Judy Mills of the International Tiger Coalition.

"The World Bank's involvement has the potential to catalyze a paradigm shift for wild tigers and their habitats."

From 100,000 a century ago to an estimated 4,000 today, the initiative reports wild tigers are seriously threatened by poaching and loss of habitat.

Experts say poaching for parts, traditional medicines and for meat is the animals' primary threat, followed by the loss of natural habitat.

Currently, tigers now inhabit less than seven per cent of their historical range.