Vice President Joe Biden visited a military training centre in Afghanistan on Tuesday to review the effort to prepare Afghan forces to take over from the US-led coalition by the end of 2014.During the visit to the Kabul Military Training Centre just outside the capital, Biden was briefed on the program, which is costing 20 billion dollars over 2010 and 2011.The program is also teaching recruits to read and write, as only 11 per cent of enlisted personnel and 35 per cent of noncommissioned officers in Afghanistan's army andpolice are literate.Biden later travelled to the presidential palace where he was to meet President Hamid Karzai. He was accompanied by the top military commander in Afghanistan, Gen David Petraeus, and the US ambassador.The coalition hopes to train about 300,000 army and police officers by the end of the year. The Afghan army now has 149,553 personnel and is projected to grow to 171,600 by October, according to NATO figures.The US plans to begin withdrawing combat forces from Afghanistan in July but remains concerned that gains made in the nearly decade-long war could be reversible.