VIENNA, Austria - Western diplomats and nuclear experts voiced growing concern Tuesday that Iran has reneged on its promise to fully suspend uranium enrichment _ a process that can be used to make nuclear weapons.

Worries over Tehran's nuclear intentions coincided with decreased concern among nuclear watchdogs about Libya's nuclear ambitions. Tripoli volunteered last month to give up chemical, biological and nuclear weapons or weapons programs.

Disarmament teams are in Libya to start dismantling the country's weapons of mass destruction, and diplomats say the North African country apparently was sincere in its vow to disarm.

The most recent developments threaten, therefore, to put Iran at center stage at the next top-level meeting of the International Atomic Energy agency in March.

Tehran announced it had suspended uranium enrichment late last year as it sought to blunt international concern it was running a secret weapons program and to defang U.S. attempts to gain U.N. Security Council involvement.

Now, diplomats told The Associated Press on condition of anonymity, even key European nations who negotiated the deal with Tehran have started to question Iran's commitment because it appears to be using semantics _ the meaning of the word suspend _ to keep some of its nuclear enrichment program operational.

The IAEA last fall asked Iran to stop "enrichment-related activities." But while Tehran has stopped introducing uranium into enrichment equipment, it continues to make and assemble that equipment _ centrifuges used to spin uranium into low grade fuel for peaceful use or high-grade material, for weapons.

If the Iranian program becomes central at the March IAEA meeting, the issue could pit Washington against France, Germany and Britain, which secured Iran's suspension pledge last summer in exchange for a promise to ease restrictions on technology exports to Tehran.

"We fully expect the next board meeting will discuss the matter," said one of the diplomats.

"They have been clearly called on to adopt a comprehensive suspension of all enrichment activities, so naturally that's what we will discuss in March."

The United States interprets suspension as encompassing the whole process _ including a halt in assemblage of enrichment equipment. U.S. State Department spokesman Richard Boucher warned last week that failure by Iran to indefinitely suspend "all enrichment-related and reprocessing activities would be deeply troubling."

The IAEA continues to negotiate with Iran on what constitutes suspension, but one diplomat told AP that Mohamed ElBaradei, the agency's director general, "feels strongly" that Iran should also stop making and assembling centrifuges.

While the European Union has not commented publicly, diplomats familiar with the issue told AP it is also an EU concern.

They said Javier Solana, the European Union's foreign policy chief, brought up the continued manufacture of centrifuges with Hasan Rowhani, head of Iran's powerful Supreme National Security Council, during his visit to Tehran last week. The French also raised the issue Thursday, when Rowhani visited Paris, the diplomats said.

For his part, Rowhani suggested Iran would not expand its narrow interpretation of what constituted an enrichment embargo _ and pointedly urged the Europeans to deliver on promises of increased technological aid.

"Iran will not accept restrictions on its peaceful nuclear program," he said, while in Paris. "Iran expects its European friends to honor their commitments."

One of the diplomats suggested an oversight on the part of France, Germany and Britain when they made their deal with Iran.

"Right from the beginning, everybody asked, 'what is suspension,' but the Europeans and Iranians never defined it," he said...