Warsaw — The United States prescribed expensive medicine for aging NATO on Tuesday, pressing alliance defence ministers to build a high-tech strike force of 20,000 for the war on terrorism and other security challenges.

European allies welcomed the idea, but some expressed concern that it could compete with — or even undermine — the European Union's fledgling Rapid Reaction Force.

France took a tough stance, saying that NATO should not operate outside its own borders and that the new force should get a green light from the UN Security Council every time it acts, a position that U.S. officials called a "semantic problem."

U.S. Defence Secretary Donald Rumsfeld said he received an overwhelmingly positive response to his blunt warning that NATO could wither and die if it did not prepare for attacks like those in the United States on Sept. 11, 2001.

"If NATO does not have a force that is quick and agile, which can deploy in days or weeks instead of months or years, then it will not have much to offer the world in the 21st century," Mr. Rumsfeld said at a meeting of NATO defence ministers in Poland's capital.

If the plan is endorsed by ministers and accepted by heads of state at a November summit in Prague, NATO could within two years begin building a land, sea and air force of European and U.S. troops ready to deploy in seven to 30 days.

The mixed units of troops from both Europe and America, including rotating brigades of about 5,000 members each, would have high-tech arms such as satellite-guided bombs and could protect themselves against chemical and biological attack.

"We believe in this alliance and want it to succeed," Mr. Rumsfeld said, cautioning that if NATO failed to modernize and improve its military capabilities "it would send a harmful signal to the world about our alliance."

Competition with EU?
NATO Secretary-General Lord George Robertson said the idea was warmly welcomed and seen as "not duplicating or replacing other national or multinational forces."

It would help the alliance's drive to reinforce and refocus its military capability and streamline its cumbersome Cold War-era command structure, Lord Robertson said.

"I think this is a very good idea," Italian Defence Minister Antonio Martino told Reuters as he arrived for the meeting. "It must be evaluated in the framework of all the other commitments we have with NATO and the European Union."

U.S. defence analyst Barry Posen, a visiting fellow at the Transatlantic Centre in Brussels, said Mr. Rumsfeld's proposal could divert crack troops committed to the EU's 60,000-strong Rapid Reaction Force, an as-yet untested project due to be fully operational next year.

"I suspect it's a cream-skimming operation in which NATO will cream off the best European capabilities," Mr. Posen told a seminar in Brussels. "It seems to me that this is a revolver pointed at the EU's Rapid Reaction Force."

He questioned whether the entire proposed NATO force would ever be used in action, since the Bush administration had a clear preference for engaging individual allies in action under its command rather than working under NATO auspices.

The United States insists that it is not trying to elbow aside the EU, and says it merely wants to give NATO — which has so far played a minor role in the U.S.-led war on terrorism — the means to respond quickly in far-flung trouble spots.

The EU force, on the other hand, could be dedicated to peacekeeping and conflict prevention in Europe's neighbourhood.

French Defence Minister Michele Alliot-Marie said Paris was not opposed to the idea, but she said the force must always have UN Security Council authorization to act and NATO should not take on missions beyond its own borders.

"We mustn't lose sight of what motivated the creation of NATO from the start," she said. "NATO must cling to its original geographical purpose."