US vice president-elect Joe Biden and President Hamid Karzai met for several hours Saturday, discussing all aspects of US help for Afghanistan's efforts to fight extremists and rebuild, an official said. Biden was in Kabul on a short visit 10 days before he was due to take office alongside president-elect Barack Obama, who has said Afghanistan will be a priority for his administration. The senator's meeting with Karzai was "fruitful and productive" and included commitments to continued cooperation in the war against terrorism, the Afghan president's spokesman Homayun Hamidzada told a foreign news agency.