ElBaradei called on countries around the world to spend the money necessary to ensure that their nuclear plants could withstand terrorist attacks.

Although the majority of European countries with substantial nuclear power production say they are reviewing security measures in light of the September 11 attacks in the United States, they are reluctant to say exactly what they are doing.

So far, it is not clear to what extent security has been improved in countries like Britain, Germany, Russia and France, which produce a large amount of their electricity from nuclear plants.

WASTE REPROCESSING PLANTS

Reprocessing plants such as BNFL's Sellafield plant in Britain and French Cogema's plant at La Hague in Normandy are said to be particularly prone to attack because reprocessing creates a higher level of radioactivity.Both plants process nuclear waste from a number of countries. BNFL, which also runs nuclear generating plants, declined to comment on improvements in security but said it had put in place whatever measures were required by the nuclear watchdog, the Office for Civil Nuclear Security (OCNS).

"We do what we're told by our regulator. For security reasons, we cannot give details of measures taken," said a BNFL spokesman.

The Department of Trade and Industry, which handles press inquiries for the OCNS, was no more specific.

"We've always applied the stringent international rules on nuclear plant safety. We've taken the extra threat on board and are reviewing security at installations," said a DTI spokesman.

He declined to say whether additional measures had been taken since the September 11 attacks on the United States, but confirmed that no military equipment, such as ground-to-air missiles, had been put in place.

"That's not to say it's not being looked at," he said.

Pressure to improve security measures at Sellafield was intensified last month after a European Union report said an accident at the plant could cause greater damage than the Chernobyl explosion in Ukraine in 1986, which exposed more than five million Europeans to increased levels of radiation.

Nuclear power accounts for 27 percent of Britain's overall electricity generation.

So far, only the French government has said it has taken drastic measures to strengthen security at nuclear facilities.

Two weeks ago, the French defence ministry announced it had deployed ground-to-air missiles near the plant at La Hague as a precaution after the hijacked airliner attacks on the United States.

It also said it was prepared to use warplanes to shoot down hijacked aircraft and boosted security around key sites such as nuclear plants, industrial zones and large dams. It did not give further details of measures it had taken.

France is Europe's largest nuclear power producer, its 19 nuclear power sites producing 76 percent of its electricity.

In Germany, where nuclear power accounts for one-third of national needs, Environment Ministry spokesman Martin Waldhausen said power companies had tightened plant security after the September 11 attacks, but no extra security measures had been ordered recently because there were no indications of a threat.

A debate began last month on whether to switch off old German nuclear plants sooner than initially planned after the Commission on Nuclear Reactor Safety (RSK) said in a report that older nuclear plants could not withstand a suicide plane crash.

In Russia, where concern has focused more on military nuclear targets, the government said it was not aware of a specific threat to civil installations.