WASHINGTON — The Obama administration is considering keeping a force as small as 3,000 to 9,000 troops in Afghanistan after 2014, U.S. officials said Saturday.

The new options under consideration are smaller than the 6,000 to 20,000 troops Gen. John Allen, the U.S. commander in Afghanistan, is said to have previously suggested.

These potential alternatives were produced by the Pentagon at the behest of the White House and reflect a familiar pattern within the Obama administration on the use of force. Sensitive to public opinion and budgetary pressures, the White House has generally favored lower troop levels during its previous deliberations on Afghanistan and Iraq.

The military, by contrast, has tended to favor somewhat higher numbers, because of the greater risks posed by a smaller force carrying out its mission in a rugged and hostile environment like Afghanistan. In this case, the Pentagon believes that the 9,000-troop option - the upper range of the new scale - is more realistic, officials said.

The new troop options were first reported Saturday by The Wall Street Journal, which said they would leave approximately 3,000, 6,000 or 9,000 troops in Afghanistan after 2014, when NATO nations are scheduled to hand over responsibility for security to the Afghans.

The Obama administration’s deliberations over troops come as Afghanistan’s president, Hamid Karzai, is preparing to visit Washington early this week. The United States and Afghanistan began talks in November on a possible agreement that would authorize a U.S. troop presence in Afghanistan after 2014.

Any force that remains is expected to have several missions. It would include Special Operations forces, which would be assigned to carry out raids against al-Qaida and other terrorist groups that are deemed to threaten U.S. interests.

The troops would also advise and mentor the Afghan army and police in conjunction with forces from other NATO nations.

In addition, any U.S. force that remains needs to be able to support itself logistically, to have the ability to carry out medical evacuations and to conduct airstrikes to protect any NATO troops that might be in danger.

A White House decision to field a minimal force might add to the already formidable list of difficulties with Karzai. The Afghan leader might see a minimal force as an indication that the United States is less interested in advising and training Afghan troops than in retaining the capability to carry out operations against terrorist groups.

The Taliban have also sought to influence the debate over U.S. troop levels. In a statement issued Saturday, the Taliban warned that they would continue the war if any “residual” troops remain, according to the SITE Intelligence Group, which monitors terrorist organizations and their communications.

The number of troops to retain in Afghanistan after 2014 is not the only decision facing the White House. It also needs to decide how quickly to withdraw the 66,000 troops currently in Afghanistan and how many troops to keep there in 2013.

Two U.S. officials said last year that Allen wanted to keep a significant military capability through the fighting season ending in fall 2013, which might translate to a force of more than 60,000 troops until the end of that period. The White House is believed to favor faster reductions.

Front Section, Pages 11 on 01/06/2013