Secretary of State Colin L. Powell said today Pakistan understands that "consequences" will apply if the United States discovers that the Pakistani government continues to make suspect nuclear transfers to North Korea.

Powell's statement, made to reporters while traveling here for a conference with Mexican officials, suggested a public hardening of the administration's stance toward its ally in the fight against terrorism. Previously, Powell had said that he had been assured by Pakistan that it is not currently engaging in such transactions, but he had not raised the possibility of U.S. action against Pakistan.

Powell has privately delivered this message to the Pakistani president, Gen. Pervez Musharraf, making it clear that the United States would be watching Pakistan's behavior closely.

"In my conversations with President Musharraf in recent months, I have made clear to him that any, any sort of contact between Pakistan and North Korea we believe would be improper, inappropriate and would have consequences," Powell said. "He has assured me on more than one occasion that there are no further contacts."

The administration has evidence that Pakistan continued to receive missile parts from North Korea in exchange for possible nuclear plans and materials as recently as three months ago, according to reports in Washington last week. Powell said today he could not discuss reports of recent transactions.

Since the administration confronted North Korea with evidence of its secret program to build nuclear weapons using enriched uranium, officials have sought to isolate the communist state until it agrees to dismantle the program. But officials have taken a much softer stance against Pakistan, despite increasing evidence that it played a key role in the development of the North Korean program. In large part, this is because officials believe it is essential to maintain Pakistan's cooperation in the war against terrorism.

"President Musharraf understands the seriousness of the issue," Powell said, adding that he has discussed it both "face-to-face" with Musharraf and on the phone, including several times in the past month. "Whenever he and I communicate with each other, I reinforce the point," Powell said.

Under U.S. law, a nation must face sanctions if it allows the transfer of uranium enrichment technology without international safeguards, unless the president issues a waiver. "There are laws that apply, and we will obey the laws," Powell said. He declined to specify exactly how Pakistan would be sanctioned if the illicit trade continues.