The Department of Transport says the LE Aoife is expected to reach a tanker stranded off the north Kerry coast by about midnight.
An operation has been under way all day, headed by the Irish Coastguard, to make arrangments to take the ship, the 'West Sailor', to safe anchorage in one of the Shannon Estuary ports. The Fenit lifeboat remains on standby.
Meanwhile, the crew of 15 remain on board. Conditions at sea are described as excellent and very calm.
The 95m long vessel, which unloaded its cargo of sulphuric acid at Aughinish Alumina yesterday, is anchored 5km off Brandon Head on the north Kerry coast.
12 members of the Dublin Fire Service trained in marine emergency response were on standby at Kerry Airport from early today but have returned to base.
The Maltese-registered 'West Sailor' was travelling from the Shannon Estuary to Belgium when it was disabled 16km north of Brandon Head.
A blaze was reported on board the vessel shortly after 2am this morning but was contained by the 15-strong crew.
Crew members are carrying out an assessment of the damage caused by the fire, which broke out in a storeroom in the engine room.
The ship had delivered a cargo of sulphuric acid to the Aughinish Alumina plant on the Shannon Estuary yesterday.
ITF to inspect vessel
International Transport Federation Inspector Ken Fleming, of SIPTU, is to inspect the bulk freighter after it is towed into the estuary.
Mr Fleming will be seeking to establish the sequence of events from the time the ship caught fire until it was brought under tow by the rescue services.
The ITF says a message received from the ship suggests that the crew were not permitted to call the emergency services for help.
He will also be investigating pay and working conditions on board the vessel.
The ITF said the immediate priority is to ensure the safety of the crew, who are thought to be Filipino, and ensure they are receiving their proper pay and conditions.
