Iran is attempting to draw up plans to strike targets in Europe and has conducted reconnaissance of European nuclear power stations, a security analyst told a meeting at Britain's parliament Tuesday.

Claude Moniquet, president of the European Strategic Intelligence and Security Center, a private think-tank in Brussels, said his organization also had evidence Tehran has increased numbers of intelligence agents across Europe.

"We have serious signals that something is under preparation in Europe," Moniquet said. "Iranian intelligence is working extremely hard to prepare its people and to prepare actions."

The center, which he said deals directly with European intelligence agencies, believes Iranian operatives have carried out "reconnaissance of targets in European cities, including nuclear power stations," Moniquet said. He mentioned no other specific targets.

Preparations to target Europe's nuclear energy plants could be tied to the diplomatic standoff over Tehran's contested nuclear program, he told a meeting of lawmakers and analysts in London's House of Commons.

Iran appeared to be preparing to target "British citizens on the streets of London," Moniquet said. "Just as they kill British soldiers in the south of Iraq."

Conservative lawmaker Patrick Mercer told the meeting that Foreign Secretary Margaret Beckett, in a debate in December, had acknowledged worries about Tehran backing terrorist activity inside Britain.

There were "concerns about the scale and nature of terrorism in this country, and about whether some of that is inspired or funded in any way by forces in and around Iran," Beckett told lawmakers.

Parliament's intelligence and security committee, a panel of lawmakers which reviews work of Britain's MI5 and MI6 domestic and foreign spy agencies, also warned last year of an "increased threat to U.K. interests from Iranian state-sponsored terrorism."

A government security official, who demanded anonymity because of the sensitive nature of intelligence work, said Iran was active in espionage and likely interested in compiling information on European military and industrial targets.

However, the official could not verify Moniquet's claim that Tehran had conducted reconnaissance against power plants or increased numbers of agents in Britain.

"There was a lot of anticipation the number of agents would increase when President (Mahmoud) Ahmadinejad came to power," the official said. "But I'm not sure whether that has actually been the case."

Officials at Iran's London Embassy did not immediately return calls requesting comment on Moniquet's claims.

Mercer called for tougher sanctions against Tehran from the U.N. Security Council, to force Iran to halt its nuclear program and to dissuade the regime from backing militia groups attacking British forces in Iraq and Afghanistan.

Opposition Conservative party leader David Cameron also urged Britain and the United States, in an earlier speech Tuesday, to strengthen measures against Iran and called on Washington to speed up plans for talks with Iranian officials.

The Vienna-based International Atomic Energy Agency is due to submit a report on Tehran's program to the U.N. Security Council on Wednesday and is expected to reveal further Iranian advances in uranium enrichment.

In March, Tehran was given a 60-day deadline — which expires this week — to halt enrichment or face further punitive measures.

Iran insists it is engaged in a civilian power program. The United States and its allies claim it is a cover for the covert development of nuclear weapons.

Current sanctions are "too weak to bring about a change in behavior" and incentives to halt the program — such as the prospect of better relations with the West — have been damaged by a lack of commitment by the United States, Cameron said.

Talks are scheduled in Baghdad between U.S. Ambassador Ryan Crocker and his Iranian counterpart on May 28, and will be among only a handful of direct U.S.-Iranian talks since the 1979 hostage crisis.