Berlin: Secretary of State Hillary Clinton on Thursday backed further away from a US timeline to start pulling troops from Afghanistan in July, warning "political expediency" would benefit the Taliban.
Speaking at a NATO foreign ministers meeting in Berlin, Hillary also warned of a "violent spring fighting season" in Afghanistan as the Taliban try to exert themselves in areas where Afghan forces are due to assume control.
"We have to steel ourselves and our publics for the possibility that the Taliban will resort to the most destructive and sensational attacks we have seen," she said.
Hillary hailed the "heroic sacrifices" by nations in the International Security Assistance Force in Afghanistan, and insisted there has been progress in fighting the insurgents.
"We need to ensure that these sacrifices are not overtaken by political expediency and short-term thinking," Hillary told the NATO meeting in Berlin.
"We need to worry less about how fast we can leave and more about how we can help the Afghan people build on the gains of the past 15 months," she said.
President Barack Obama has tripled US troops in Afghanistan to 100,000 since taking office in 2009 but had promised to begin a drawdown in July. The nearly 10-year-old war has become unpopular in the United States and allied nations.
Foreign ministers of nations involved in Afghanistan met for three hours, hearing on-the-ground assessments from General David Petraeus, the top US commander in Afghanistan, along with Afghan Foreign Minister Zalmai Rassoul, according to a US official.
Hillary said that Afghanistan was seeing real, but reversible, progress and pointed to President Hamid Karzai`s March announcement that Afghan forces would assume security in key areas including the southern province of Helmand.
"For the transition to be sustainable and irreversible, and for reconciliation and diplomacy to bear fruit, we must sustain our efforts," Hillary said, according to her prepared remarks.
"We need to underscore that we are transitioning, not leaving," she said.
Despite public opposition, Obama`s Republican political foes have attacked him over the July deadline, saying it would be the wrong signal to the Taliban and discourage neighbouring Pakistan from acting against insurgents.
The Obama administration has gradually de-emphasised the timeframe, instead saying that most US forces would leave in 2014 -- the date set by last year`s NATO summit for putting Afghans in charge of their own country`s security.
Hillary appeared to de-emphasise that date as well, saying that the United States was committed to "building an enduring partnership with Afghanistan that will last well beyond 2014”.
"The Taliban need to know that they cannot wait us out," Hillary said.
Critics of the war, including lawmakers in Obama`s Democratic Party, scoff at assessments of progress, pointing out that last year was the deadliest in Afghanistan for both Afghan civilians and the US military.
Support for the Afghanistan war, launched in pursuit of al Qaeda after the September 11, 2001 attacks in the United States, has also dwindled among US allies.
But Hillary renewed a US call for NATO nations to drum up USD 1 billion to help sustain the Afghan National Army.
While keeping up the military effort, the Obama administration has also embraced efforts for reconciliation in Afghanistan, concluding that there is ultimately no political solution to the conflict.
Hillary`s robust call on Afghanistan came at a NATO meeting dominated by Libya, where France and Britain have taken the lead and sought greater support from NATO allies.