WASHINGTON (Reuters) -- U.S. President Barack Obama could eventually send five combat brigades to Afghanistan, including one devoted wholly to training the Afghan army, Pentagon officials have said.
The White House is expected to announce up to three new brigade-size deployments for Afghanistan as early as next week to help meet a long-standing request for additional forces from field commanders.
The Obama administration is examining plans to send as many as 30,000 extra troops overall in the next 12 to 18 months to quell violence that has surged to the highest levels since the 2001 U.S.-led invasion that toppled the Taliban regime.
The Pentagon has talked of adding four combat brigades -- units of about 3,500 soldiers. But a fifth could be deployed later this year to train Afghan troops, according to officials who stressed that the planning was subject to revision.
Small groups of soldiers from the brigade would be assigned to operate within Afghan army units as part of a training and mentoring program intended ultimately to have Afghan soldiers lead security operations.
"That's what's being looked at right now," said one official.
Some extra U.S. troops have already begun arriving in Afghanistan, including 3,700 soldiers from a combat brigade of the Army's 10th Mountain Division that deployed this month.
The three brigades expected in Obama's announcement would include a large Marine task force and would increase the number of U.S. troops to the Afghan combat zone by up to 17,000.
Add to that an additional 5,000 support troops heading for Afghanistan and the United States could wind up sending a total of 25,000 extra forces by mid-summer, officials said.
There are currently 36,000 U.S. troops in Afghanistan, including 17,000 under NATO's 55,000-strong International Security Assistance Force.
Top military officials say more Western troops are needed in Afghanistan to buy time until an effective Afghan army and police force can take over security in the country.
The current plan, intended to put an Afghan "face" on the struggle against the Taliban and other militant groups, is to grow the Afghan army to an active force of about 134,000 soldiers from about 84,000, according to U.S. officials.