Illegal Moldavian migrants landed near Rome last Thursday

Pressure for exemplary action came from the Northern League, whose more extreme members have in the past suggested opening fire on smugglers' boats.

The defence ministry has said there is no possibility of this.

Navy vessels will, however, be authorised to intercept boats, personnel will go on board to inspect them, and later - if they are proved to be involved in illegal activities - they will be destroyed.

The navy has always been used to patrol the seas around Italy, but since a tragic accident four years ago, they have simply alerted the coastguard to suspect vessels while keeping their distance.

On Good Friday in 1997, an Italian navy Corvette accidentally rammed a trawler, and more than 80 Albanians, including many women and children, drowned.

'Demagogy'

Massimo Bruti, a former defence under-secretary and left wing senator, said the new moves were dangerous as the risk of collisions would be high.

Other opposition MPs have dismissed the initiative as 'demagogy' - playing up to populist opinion.

However, a telephone poll of 1,300 Italians on Friday showed a surprising 70% favoured giving the navy police powers to tackle immigration.

Last week, another rusting vessel with 450 people on board, most of them Kurds, arrived on Italy's southern coast, and the police here say that with the warmer weather coming, they expect there to be more and more arrivals.