A campaign by environmentalists in Australia to prevent uranium mining in one of the country's biggest national parks has gone a step further, with the beginning of a visit to the area by United Nations experts.

They will decide whether to put the Kakadu National Park in northern Australia on a list of endangered world heritage sites.

In recent months, protesters have blockaded the site, which is popular with tourists for its Aboriginal cave paintings and rare animals.

The campaigners believe that a decision to list the park as an endangered site would put the government under pressure to scrap the mining plans.