The top American diplomat for Pakistan, Richard C. Holbrooke, said Friday that he would reinvigorate efforts to trace the sources of financing for the Taliban insurgency, with special scrutiny of private donations. Mr. Holbrooke said that private donors, including some from Persian Gulf countries, were increasingly believed to be a far more important source of money for the Taliban than even the opium trade, which the United Nations estimates to be about $300 million a year.

In the past there was a kind of a feeling that the money all came from drugs in Afghanistan.That is simply not true.

American intelligence officials have expressed concerns about financing for terrorism from gulf countries in the past, but Mr. Holbrooke’s remarks indicate that the United States may now seek to put more pressure on the countries to stanch the flow of money .