Although the Taliban were overthrown by an American invasion in 2001, Afghan Wireless was nevertheless the first company licensed to provide GSM wireless service in Afghanistan. With the lifting of the trade embargo, Afghan Wireless brought in technology from American vendors including WorldCom, TECORE Wireless Systems, and AirNet Communications Corporation. Afghan interim leader Hamid Karzai publicly made the first phone call on April 6, 2002, calling and speaking with the Afghan ambassador to the United Nations in New York City. As the network went public using a pre-paid platform, phone booths were set up for those unable to afford cellphones. In June 2002, Argent Networks in New Zealand was contracted to help Afghan Wireless develop its GSM mobile network. The following year Argent also developed a billing system for the network, and competing companies such as Roshan started to appear.