"We control the vast majority of the city," British military spokesman Colonel Chris Vernon said in Kuwait. "But there are some places we don't control, for example the old city."

Vernon told reporters that British tanks had moved into the city centre, the south and the north.

At least 300 Fedayeen militia fighters were estimated to have died in clashes over two days as the British surged forward, a senior officer claimed.

Colonel Hugh Blackman, of the Royal Scots Dragoon Guards, said around 150 Iraqis were killed on Saturday during fierce exchanges with his men and at least the same number died during Sunday's assault, with only "a couple of dozen" taken alive.

As the troops and tanks made their way towards the centre, locals poured out into the streets to greet their advance, many of them waving and cheering, others standing silently on pavements as the tanks passed.

Many houses had raised the white flag of surrender.

By late afternoon, the British forces had surrounded the local Baath Party headquarters in the heart of the city, a reporter for the Arabic language Al-Jazeera television station in the city reported.

There had been little sign of resistance, the paramilitary fighters who had been holding the area having apparently disappared as the troops advanced.

British commanders admitted they had expected more resistance from the Iraqis, many of whom fled across the Qamrat 'Ali bridge to safety.

Blackman said: "We leaned on the door and it burst open. This has been a crucial day."

He added: "The enemy have not been surrendering in large numbers -- they have been fighting and dying, but that is their choice."

The raid began when the so-called Desert Rats, from Britain's 7th Armoured Brigade, sent tanks and troops into the city, backed by US Cobra helicopter gun-ships and artillery, and blitzed a crucial Fedayeen HQ in a dawn raid.

As news of the success spread, a group of around 200 local men, women and children dashed out on to the streets and - for the first time - openly pointed out enemy positions.

Blackman said pro-Saddam forces "have fought hard and have been cunning and tenacious in the face of superior firepower.

"They have been using a series of ruses but have so far failed to inflict any casualties on our forces.

"There have been instances where Fedayeen fighters wearing the black suits and red head-dresses have picked up a child to give themselves cover after firing at us.

"As we advanced into Basra today they favoured a new tactic -- playing dead.

"There were several instances where we passed what appeared to be bodies lying in bunker positions only for them to spring up and attack us after we passed by.

"That led to us taking no chances as the day wore on when we were confronted with that situation."

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