Kabul, Afghanistan (CNN) -- The Taliban in Afghanistan depend on Pakistan for support, even though they do not necessarily welcome it, a secret NATO report says, according to a journalist who has read it. "It is a marriage of convenience," Times of London reporter Jerome Starkey said Wednesday, citing the report. The Taliban see Pakistan as manipulative, but they see no alternative to accepting its support, he said. The Taliban are absolutely confident of victory, he said the report found, based on 27,000 interviews with over 4,000 detainees ranging from senior Taliban commanders to Afghan civilians. They also include mid- and low-level Taliban, al Qaeda, and foreign fighters, he said.