Fighting has broken out in north-west Afghanistan between a regional commander and a provincial governor allied to the central government.
The defence ministry says it will fly 750 troops into Faryab province after forces loyal to General Abdul Rashid Dostum overran three districts.
Provincial governor Anayatullah asked the ministry to "send soldiers from the new army to stop the bloodshed".
The ministry is meeting the US military to arrange the troop transfer.
The BBC's Crispin Thorold in Kabul says that in the past Faryab has been a stronghold for General Dostum, but the provincial governor recently withdrew support in favour of the central government.
It is not clear if anyone has been killed in the fighting but a spokesman for the Ministry of Defence told the BBC the clashes were still going on.
Faryab's intelligence chief, Omayoun Haini, told the Associated Press news agency that between 2,000 and 3,000
Dostum soldiers had crossed into Faryab from neighbouring provinces on Tuesday on 200 vehicles and 400 horses.
General Dostum is an adviser to President Hamid Karzai but his forces have been involved in several territorial clashes since the fall of the Taleban in 2001.
Mr Anayatullah told the Reuters agency: "The reason Dostum launched this attack is because we obey the central government and he does not like that. He wants this province under his control."
Our correspondent says that sources in the area believe that neither the governor nor General Dostum are popular with local people, who are said to want an outside appointment.
This is the latest in a series of confrontations between strong regional commanders and the central government in Kabul.
Last month there was fighting in the western city of Herat, after the killing of Afghanistan's minister for civil aviation, who was also the son of Herat's powerful governor, Ismail Khan.