The Irish Republican Army (IRA) were terrorists who murdered people and there was nothing heroic about their struggle, Prime Minister John Howard says.

The IRA has announced its militants have been instructed to abandon their weapons, "end the armed campaign" and pursue their aims through the political process, from 4pm (0100 AEST on Friday).

Mr Howard said he would wait and see whether the IRA's pledge to end its armed struggle against British rule in Northern Ireland came to reality.

He said he was sceptical and hoped British Prime Minister Tony Blair's optimism was justified.

"The IRA were terrorists and they murdered people and the reason that the British security forces and police are so effective in responding to terrorist attacks is the bitter 30 years' experience of dealing with the IRA," he told Southern Cross Broadcasting.

"There was nothing heroic about the IRA campaign, although it is still shrouded in romanticism in the eyes of some."

The British, Irish and US governments have welcomed the statement as historic, provided the group matched its words with deeds.

(Source: Sydney Morning Herald)