VIENNA, Austria - Iran on Friday rejected UN sanctions because of its refusal to freeze uranium enrichment as invalid and warned its enemies to expect a wave of resistance if they increase pressure on Tehran to mothball the program.

The comments from Tehran and Vienna, at the end of a two-day meeting of the International Atomic Energy Agency's 35-nation board, reflected the chasm between the views of Iran and the West on what Iran needs to do to escape further UN punishment.

Ali Asghar Soltanieh, the chief Iranian delegate to the IAEA, said Security Council resolutions demanding a stop to the activity have "no legal basis."

He accused Washington of making "a political issue" of what he maintained was a program only meant to produce electricity by falsely warning of the "threat of Iran's plutonium nuclear weapon."

"Allegations ... (of) Iran's clandestine and non-peaceful activities are now proved to be baseless," he said.

In Tehran, Gen. Mohammed Ali Jafari, the head of the Revolutionary Guards, warned against growing pressure on his country in comments obliquely directed toward Washington.

"The ocean of the Iranian nation may sometimes look calm but if it becomes stormy it will create tsunamis," Jafari said.

"Enemies should know that if the Iranian nation appears patient with their plots and pressures, this is just the calm before storm," he said, adding that the country was "ready to respond to all enemy plots."

The United States has said it is pursuing diplomatic options with Tehran for now, but has not ruled out military action as a way to halt the country's nuclear program which it claims is a cover for developing weapons. Iran denies the charge, saying it seeks only to generate nuclear power with the technology.

Iran is running 3,000 declared centrifuges -- sufficient to produce enough material for a nuclear warhead within 1 1/2 years if Tehran chose to.

The IAEA meeting focused on a report from agency chief Mohamed ElBaradei outlining the progress of an investigation of past suspicious Iranian nuclear activities.

The report gives Tehran mixed marks. It suggests that as far as the agency can determine, Iran has told the truth about black market purchases of centrifuge technology used to enrich uranium.

But it points out the IAEA will be unable to assess the present state of Iran's centrifuge development unless the Iranians restore fuller inspection rights to UN experts and says it cannot draw a definite conclusion on whether some activities had possible military aspects.

The Islamic Republic asserts it is fully cooperating with the IAEA investigation, and says once that is finished, Iran will have met all obligations regarding its nuclear program.

But the United States and key European nations as well as Canada, Australia and Japan contend Iran's cooperation has been spotty, and they insist it must obey a Security Council order to suspend enrichment.

On Thursday, chief U.S. delegate Gregory L. Schulte charged that Iran was repeating past foot-dragging -- "promises of full cooperation under international pressure, selective cooperation and backsliding when the pressure comes off."

Noting that the IAEA's latest report says the agency "knows less and less" about Tehran's nuclear activities ... including whether or not it is for exclusively peaceful purposes," Schulte accused Iran of using "delay tactics" in hopes of staving off new sanctions.

To reporters, he said Iran continues "to move forward in violation of Security Council resolutions with the pursuit of technologies that can be used to build nuclear weapons." He said the council should impose further sanctions unless Iran fulfills all obligations.

Separately, Britain, France and Germany expressed concern about a recent IAEA conclusion that Iran purchased black market nuclear technology meant for Libya's military nuclear program. "This does not help reassure us," their statement said.

"We cannot accept that the knowledge of the agency in Iran is diminishing," said the statement, read by chief French delegate Francois-Xavier Deniau. "We cannot ... (accept) that Iran refuses to bend to the demands of the council and that it violates the resolutions of the Security Council."

Continued Iranian defiance means the world "has to draw conclusions at the Security Council level," the statement added, alluding to further sanctions.