But five hours after the 776-strong unit bade farewell to their loved ones and left their barracks, they were still waiting on the tarmac for US civilian contractors to begin flying them out.

Nigeria's 26th Mechanised Infantry Battalion is due to join a similar Nigerian unit already on the ground in Monrovia, doubling the size of the ECOMIL force, which is tasked with enforcing a shaky ceasefire in Liberia.

At first officers were confident that the bulk of the force would leave Thursday, but an AFP reporter at the airfield said there seemed to be some kind of delay. No official was available to explain the hold-up.

"My morale is high. We're going to save lives," declared 2nd Lieutenant Augustine Ogunedo as the troops' farewell parade ended and they said their goodbyes to relatives before mounting the trucks.

Corporal Tani Samuel, one a small number of women attached to the unit, said she was proud that her batallion had been chosen again after carrying out a similar mission to Liberia in the mid-1990s.

"It shows that what we did then was appreciated," she said.

Relatives were warned that the soldiers could be away for up to a year as their unit is likely to remain in Liberia to join a UN peacekeeping force after the west African-led mission is over.

"We're not sure how many aircraft will be available today. All the soldiers and equipment are ready to leave today if they provide enough aircraft," army spokesman Colonel Emeka Onwuamaegbu told AFP from Abuja.

The unit's armoured personnel carriers will be flown out of the southern city of Lagos, he said.

The troops are based in Sokoto and are due to be flown out in planes operated by US contractor PAE as part of Washington's 10-million-dollar (8.8-million-euro) assistance package to the peacekeepers.

ECOMIL's Nigerian commander General Festus Okonkwo already has one Nigerian battalion on the ground in Liberia, along with a small number of Ghanaian troops providing security for his headquarters.

In addition, some 200 US Marines arrived outside the Liberian capital Monrovia on Thursday to help ECOMIL secure the port area and provide a gateway for humanitarian supplies to the beleaguered city.

The rebel Liberians United for Reconciliation and Democracy (LURD) had agreed to hand over the port to peacekeepers and on Thursday the first ECOMIL troops arrived in the port and formally took charge of it as rebels pulled out of the city.

The new battalion's arrival will double the current size of the ECOMIL west African peacekeeping force in Liberia to more than 1,500 troops.

It is eventually expected to grow to between 3,000 and 5,000 personnel and is due to be replaced by October with a UN peacekeeping force, probably containing some of the same ECOMIL units.

The previous Nigerian deployment came from troops already deployed with the UN peacekeeping force in Liberia's neighbour Sierra Leone, and Thursday's airflift will be the first from Nigeria itself.

Liberia has been wracked by almost-continuous conflict for the past 14 years, but hopes have been raised that the latest five-year civil war might soon come to an end.

Former warlord Charles Taylor resigned as president on Monday and went into exile in Nigeria. His successor, former vice-president Moses Blah, has travelled to Ghana to meet rebel leaders for talks on a peace deal.

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