Government forces in Liberia say they have launched a counter-attack after the country's second city was taken by rebels.
Conditions for civilians worsen as fighting continues
Defence Minister Daniel Chea told the BBC that there was street fighting in Buchanan as the army tried to prevent the rebels from bringing in supplies.
Meanwhile, the main rebel group, Liberians United for Reconciliation and Democracy (Lurd), has announced a ceasefire. Previous such declarations have not ended the fighting.
The sea port of Buchanan fell to the Movement for Democracy in Liberia (Model) - Liberia's second largest rebel force - on Monday.
Aid agencies warn that this will make it difficult to get food supplies to the many thousands of refugees in Liberia.
"Buchanan was the only alternative way to ship some food into Liberia. Now - you can forget about it," Frederic Bardou said at a feeding centre in Monrovia run by Action Contre la Faim, or Action Against Hunger.
The government no longer has access to a sea port, although it does still control the main international airport. The main rebel group controls the port in the capital, Monrovia.
As the fighting continues, West African officials say it is unlikely that there can be an imminent deployment of regional peacekeeping troops.
Officials from the regional body, Ecowas, said the fighting was preventing even the despatch of a reconnaissance mission.
Some 1,300 Nigerian troops are on standby to be transferred to Liberia.
But Nigeria's President Olusegun Obasanjo says his country needs more outside help to bear the financial and logistical burdens of leading the operation.
While Model has entered Buchanan, Lurd has taken the eastern town of Gbarnga, Mr Taylor's base during the 1990s civil war.
Clashes between government forces and Lurd also continued around two key bridges in Monrovia, which lead to the city centre.
Lurd spokesman Joe Wylie urged Mr Taylor to step down to avoid the unnecessary loss of life.
"He's getting weaker and weaker... He should not face us in a final military showdown that will just take lives," he said.
The fighting is causing desperate problems for civilians in the war-torn country.
Thousands of Liberians had fled to Buchanan to escape the fighting in Monrovia, where hundreds have been killed and thousands injured in a 11-day assault by rebels.
Buchanan residents say there was a lot of shooting overnight as looting took place.
The BBC's Paul Welsh in Monrovia says that battles are almost invariably followed by robbery in this war.
The rebels are trying to overthrow President Charles Taylor, who has been indicted by a United Nations-backed war crimes tribunal in Sierra Leone.
He has agreed to quit and accept asylum in Nigeria if peacekeepers come to Liberia.
West Africans want the peacekeepers to be led by United States troops and three US warships are heading for the Liberian coast.
But President George W Bush says the troops will not land until a ceasefire is in place.
The United Nations Secretary General Kofi Annan has warned the rebels they are disqualifying themselves from playing a role in the country's political future by continuing their military offensive.
The rebels have rejected a US plea to both sides to respect a ceasefire and for the rebels to withdraw to the River Po, 12 kilometres (seven miles) from central Monrovia.
Water and food are running short for residents of the capital, whose numbers have been swelled by up to 250,000 refugees.