The Australian Democrats have called for the immediate recommissioning of Radio Australia's Darwin transmitter to improve the signal strength of broadcasts to Cambodia, where an estimated 517 Australians are trapped.

Senator Vicki Bourne, Foreign Affairs and Broadcasting Spokesperson for the Democrats, said "Radio Australia's (RA) transmitter, on the Northern Territory's Cox Peninsula, was closed by the Federal Government last week. RA's programmes are now transmitted via Shepparton in Victoria, resulting in a much weaker signal to huge parts of Asia, including to Cambodia.

"Most of the 517 Australians in cambodia are in the capitol Phnom Penh where the fighting is centred.

"These Australians have been advised by our Ambassador, Mr Tony Kevin, to remain in their homes. Mr Kevin has requested they remain alert and has suggested they tune in to BBC or Voice of America.

"Why should Australians in a crisis have to tune into a foreign news service when we have the capacity to speak to them directly through our own RA?

"In such crises short-wave radio transmission is absolutely critical because of its relative immunity from disruption and jamming by warring factions.

"Improved RA signal strength is the most sensible way of transmitting to these Australian citizens. Without being alarmist, a weaker RA signal makes the already difficult job of contacting and perhaps evacuating Australians from the war torn area, unnecessarily harder.

"Unfortunately, less than one week after its closure, this crisis proves that the decision to close the Cox Peninsula transmitter was wrong and basically stupid.

"I urge the Government to immediately reverse that decision and to allow RA to do its job with the effectiveness and efficiency for which it is so widely respected. Australian and Cambodian lives may depend on it."