Negotiators have begun the delicate task of liaising with the hijackers of an Afghan plane at Stansted airport.

David Learmount, operations and safety editor of Flight International, told BBC Online that the negotiators will concentrate on small deals and not negotiate the hijackers' ultimate aims.

He said they would be talking to the hijackers in a friendly but dispassionate manner and that all requests would probably be dealt with slowly.

"The most important thing is not to be in a hurry," said Mr Learmount. "Everything the hijackers ask for, they will be told by the negotiators that they will see what they can do.

"If they ask for something as simple as a glass of water or for the lavatories to be emptied, the strategy is to take time in the hope that eventually the hijackers will become worn down."

Triumphs

He said the technique is to concede things that do not matter, so that even getting a glass of water appears to be a triumph.

He says, for example, it took almost five hours on Monday morning to get a generator to the plane to power the air conditioning.

"They will continue negotiating for small things until it becomes a question of negotiating about survival," said Mr Learmount. "Eventually, they will have to remind themselves about the bigger picture - what they had originally set out to negotiate for."

He said there is usually a psychologist advising the team of police negotiators.

The team will have to watch the hijackers carefully to make sure they do not become desperate. If they do, tactics will change, says Mr Learmount.

In contrast to past hijacking situations, Mr Learmount said it was unusual that police with weapons appeared in sight of the plane's cockpit.

"The hijackers will know there are armed police around," he said. "Generally they never let the hijackers see that the forces are gathering."