US Secretary of State Hillary Clinton heads to Pakistan in the coming days to bolster support in the fight against the Taliban and outline a political endgame to the war in neighboring Afghanistan. As she heads to a donors' conference in Kabul set for Tuesday next, Clinton was expected to press her counterparts to step up their efforts against the insurgents. She will also discuss reconciliation efforts between Afghan President Hamid Karzai's government and reconcilable elements of the Taliban. But Washington considers Islamabad's role in the effort ambiguous and opaque at this point, according to the US envoy to Afghanistan and Pakistan, Richard Holbrooke. Pakistan may be a crucial US ally against extremists in the region, but it also harbors a major contingent of Taliban fighters and their Al-Qaeda allies, who are killing more international forces in Afghanistan than ever before in the nine-year war.