WASHINGTON: Allied and Afghan forces are putting a greater focus on going after the Haqqani militant network, which has threatened to disrupt the Afghan presidential elections in April, the top US commander in Afghanistan said Thursday.

Marine Gen. Joseph Dunford told Defence Department reporters that the more energised effort against the Haqqanis includes a US move to “crank up the heat” on the group's financing and freedom of movement.

“The Haqqani network has been more active in some ways over the last few months, and so we have energised our efforts accordingly,” said Dunford.

The network has made it clear it will conduct high-profile attacks to disrupt the political process and create the perception of insecurity as Afghans go to the polls.

The Haqqani network is blamed for some of the most high-profile attacks in Afghanistan.

The US has repeatedly pressed Pakistani authorities to move more aggressively against the militants, who are allegedly based in North Waziristan and routinely to conduct attacks against US and coalition troops.

Dunford also gave reporters and lawmakers greater details on the US plans as the war winds down and combat operations end on Dec 31.

Officials have long said the coalition of Nato and allied nations would leave 8,000 to 12,000 troops in the country to advise and assist Afghan forces as long as Afghanistan's leaders sign a key security agreement. In addition to that, Dunford said the US would leave “some thousand” troops — largely special operations forces — to continue to conduct counterterrorism operations.

He said that any US counter-terror operations beyond 2014 would focus on Al Qaeda, but since the Haqqani network presents the greatest threat to security forces, the US would do whatever necessary to protect the troops.

US officials have said they want to leave about 10,000 troops in Afghanistan, but it's not clear if the counterterrorism forces would be in addition to that.

Afghan President Hamid Karzai, however, has refused to sign the agreement, prompting the White House to order the Pentagon to begin planning for a full withdrawal by the end of this year.

Dunford told members of the House Armed Services Committee on Thursday that he would need 102 days to conduct an orderly withdrawal of all US troops and equipment and complete the transfer of any bases to the Afghans.

As a result, he said the US can wait until September for the Afghans to sign the agreement, but waiting beyond that would begin to make the withdrawal far more risky.

The Pentagon is currently planning to cut the total American force in Afghanistan to as low as 20,000 by midsummer, giving commanders the ability to pull all troops out by Dec 31 if no agreement is reached. There are currently about 33,600 US troops in Afghanistan.