WASHINGTON (Reuters) - Afghan President Hamid Karzai has banned US government advisers from the Afghan central bank, where they have worked for years to help develop the country's financial sector, a US watchdog said on Wednesday. The atmosphere at the bank had become "hostile" for US government advisers helping to train Afghan bank regulators and identify money laundering and other financial crimes, said an audit by the Special Inspector General for Afghanistan Reconstruction, known as SIGAR. The special inspector general was created by Congress to scrutinise how US aid to Afghanistan is spent. The pushback from Karzai was part of a pattern of uneven Afghan cooperation with US efforts to bolster Afghanistan's fledgling financial institutions and safeguard billions in US cash that has poured into the country during the Afghan war, the SIGAR audit said. Congress has appropriated over $70 billion since 2002 to implement security and development aid projects in Afghanistan.