If Iftikhar Chaudhary Khan is telling the truth, Pakistan has nuclear weapons aimed at targets in India and has considered a first strike against its neighbor.

Khan said Wednesday that he knows this because he is a Pakistani nuclear scientist familiar with his country's policy - and he is willing to tell all to U.S. officials in return for political asylum.Pakistani officials responded by calling Khan's story a hoax.

"This is a complete con job," said Salman A. Abbasy, the spokesman for Pakistan's U.N. mission. "It is a fraud."

Khan, 29, said he was prepared to describe Pakistan's nuclear program to U.S. officials in detail, including assistance that it has received from China and Iran.

U.S. officials, speaking on condition of anonymity, said it was too early to assess the significance of Khan's defection or verify his claim to be a former assistant to Dr. Altaf Hussain, director of the Khushab Nuclear Research Center in Pakistan.

State Department spokesman James P. Rubin said he had no information on Khan's claims or contacts with government officials.

Khan told The Associated Press in an interview at his lawyer's office in New York that he became alarmed after attending a top-secret meeting in April on Pakistan's nuclear strategy. He said he heard officials and scientists discuss using nuclear weapons first because of fears that India was preparing an attack with Israel's help.

Khan said he wrote a protest letter and was fired in late April. He received threats, he said, and left Pakistan in May.