The Irish Republican Army (IRA) has scrapped its weapons after more than three decades of armed struggle against British rule, the chief disarmament monitor for Northern Ireland has announced.

Gen. John de Chastelain, the head of the disarmament process, told reporters in Belfast Monday all the arms believed to be in the IRA's possession had been put beyond use.

"We have now reported to the British and Irish governments that we have observed and verified events to put beyond use very large quantities of arms which we believe are all the arms in the IRA's possession," the Independent International Commission on Decommissioning said in a statement.

The arms decommissioned included ammunition, rifles, machine guns, mortars, missiles, handguns, explosives and explosive substances, de Chastelain added.

Battles between the largely Roman Catholic IRA and its splinter groups and mostly Protestant unionists, who want Northern Ireland to remain part of the United Kingdom, have killed nearly 4,000 people since 1969 -- an era known as "The Troubles."

The IRA's move came two months after it pledged to end its campaign and get rid of its guns. The disarmament process had stalled in 2003 when it refused to allow photographic proof of the decommissioning.

CNN's Senior International Correspondent Nic Robertson said Monday's move was likely to provide an impetus to the stalled peace process.

De Chastelain, a retired Canadian general, has overseen the disarmament process under the 1998 Good Friday peace accord.

A spokesman for Sinn Fein, the political arm of the IRA, had earlier told CNN it expected the language used by de Chastelain would be able to persuade even doubters that the IRA had made good on its July promise to disarm.

Among those skeptics are the leader of the Democratic Unionist Party, 78-year-old preacher Ian Paisley, who called the IRA's July statement "a hollow gesture."

There was no immediate reaction from unionist leaders to Monday's news.

The IRA has observed a cease-fire since 1997, but the power-sharing government established under the Good Friday pact collapsed in 2002 after Sinn Fein was unable to get full IRA cooperation on disarmament.

Authorities blamed the IRA for a bank robbery late last year, and said the group was involved in a bar killing early this year that brought the ire of Britain, Ireland and the United States.

(Source: CNN)