LONDON, JAN. 30 -- Talks between British and U.S. transportation authorities over rights to fly to and from London's Heathrow airport ended today without a breakthrough, a British spokesman said.

"There is very little movement, and the U.S. cut off the talks on the grounds their negotiating mandate was exhausted," said the spokesman for the British Department of Transport.

The so-called Bermuda II talks centered on whether the two U.S. airlines -- Pan Am Corp. and Trans World Airlines Inc. -- that are now allowed to fly into Heathrow from the United States can transfer their routes to other U.S. carriers.

Both companies have agreed to sell their London rights to financially stronger carriers in deals they say are essential to their survival.

Pan Am, which is in Chapter 11 bankruptcy proceedings, plans to sell its London routes and other assets to UAL Corp.'s United Airlines for $400 million.

TWA said this week it also may have to file for bankruptcy protection from creditors if it cannot complete a similar $445 million deal with AMR Corp.'s American Airlines.

"The U.K. is content to leave things as they are if that is what the U.S. wishes, but we stand ready to continue talks," the British spokesman said.

"We had understood that this was an urgent matter for the U.S. If that is right, they will have to get a more constructive negotiating mandate and return to the table," he added.

British authorities have decided not to permit the transfers unless their U.S. counterparts make concessions. Industry analysts said such concessions could include granting Britain's Virgin Atlantic Airlines the right to fly to the United States from Heathrow rather than from London's second airport, Gatwick, as it does now.

At the moment, British Airways PLC is the only British airline allowed to fly to the United States from Heathrow.

British airlines also want to be allowed to pick up passengers when they fly from initial U.S. landing points to other airports in the country, analysts said.