WASHINGTON  - Afghan authorities have made little effort to stem the flow of billions of dollars in cash from the Kabul airport despite a US-led effort to curb laundering, a US government report said Tuesday. An earlier US study estimated that $4.5 billion in cash was taken out of Afghanistan in 2011, raising concerns that money used to finance extremist groups or generated by the narcotics trade was being stashed overseas. In 2010, the United States launched a program to help Afghanistan control the problem, particularly through greater controls at Kabul International Airport, and President Hamid Karzai’s government pledged action within a year.

But the Special Inspector General for Afghanistan Reconstruction, which was set up by Congress to monitor the more than $89 billion in US non-military aid to the country since 2001, said that little had changed at the airport. Inspectors on a recent visit found that bulk currency counters provided by the United States were not in use and not even connected to the Internet, as is necessary to transmit data. No bulk currency counters at all were available at the airport’s VIP area, even though many of the passengers suspected of laundering were believed to go through it, the report said. “The persistent delays in instituting basic anti-money laundering procedures... are deeply troubling,” it said. While acknowledging that Afghanistan has a cash-based economy, the report said that basic controls were “particularly critical for a country fraught with corruption, narcotics trafficking and insurgent activity.”