BAGHDAD (AFP) - Iraq and Britain vowed not to bargain with "terrorists" even after a Briton threatened with execution pleaded for his life, while Prime Minister Iyad Allawi spoke of success in combatting the insurgency.
Painting an upbeat picture of Iraq which stood in stark contrast to relentless violence on the ground, Allawi met with US President George W. Bush and boosted an administration which has come under fire for its shortcomings in Iraq.
Amid warnings, especially among Iraq's Shiite majority, that nothing could justify delaying the elections planned for January 2005, Allawi was adamant that the crucial vote would be held on time.
"I know that some have speculated, even doubted whether this date can be met," he told the US Congress. "So let me be absolutely clear. Elections will occur in Iraq on time in January because Iraqis want elections on time."
Speaking in English after receiving a standing ovation, Allawi told the chamber: "We are succeeding in Iraq. It's a tough struggle with setbacks, but we are succeeding.
"My friends, today we are better off. You are better off. And the world is better off without Saddam Hussein," Allawi said. "Your decision to go to war in Iraq was not an easy one but it was the right one.
His comments came after Bush's main rival in the November 2 US presidential election -- Democrat John Kerry -- lashed out at the president for taking his country to war on dubious grounds.
Kerry also said the premier was painting an unrealistically rosy picture of the situation in his homeland.
"I think the prime minister is obviously contradicting his own statement of a few days ago where he said the terrorists are pouring into the country."
In an interview with the New York Times, Allawi suggested that the surge of violence on the ground -- which has seen hundreds of people killed this month alone -- was a sign that insurgents were being defeated.
In recent weeks, a string of deadly bombings have targeted the Iraqi forces that Allawi has tasked with cracking down on the rebel pockets burgeoning across the country since sovereignty was handed over by the US occupation in June.
Iraq and Britain stood firm Thursday and ruled out any negotiation with the Al-Qaeda-linked group holding Kenneth Bigley, ignoring the pleas of the family of the engineer whose two US colleagues were beheaded this week.
In an apparent bid to influence British public opinion, the Tawhid wal Jihad (Unity and Holy War) group of Iraq's most wanted man Abu Mussab al-Zarqawi, posted on a website a video of Bigley begging Britain's Prime Minister Tony Blair to meet the kidnappers' demands.
"I need you (Blair) to be compassionate as you always said you were... I don't want to die... Please, please release the female prisoners that are held in Iraqi prisons," he said, breaking into tears.
The extremist organisation, which has already savagely executed several other foreigners and carried out dozens of deadly suicide bombings over the past year, has demanded that all women detained by the coalition in Iraq be freed.
The group's video triggered a torrent of emotional response in Britain.
Bigley's wife implored his abductors in Iraq to show mercy, in a heart-rending appeal recorded in Bangkok in her native Thai language and broadcast in Britain.
But British Foreign Secretary Jack Straw conceded there was little hope of obtaining Bigley's release, saying London would stand firm on its refusal to negotiate with terrorists.
Iraq's spiralling kidnapping drama continued to capture the world's attention with the purported execution of Italian aid workers Simona Pari and Simona Torretta, both aged 29.
A group calling itself the Jihad Organisation said in a statement posted on the Internet that it had "slaughtered" the two women, who were working for the non-governmental organization "A Bridge to Baghdad".
The Italian government said it doubted the authenticity of the statements but stressed it was still checking the reports.
An influential association of Sunni Muslim clerics in Baghdad -- the Committee of Muslim Scholars -- said that the two Italians were probably still alive and being held by a criminal gang.
As deadly attacks continued, General John Abizaid, head of the US Central Command, has acknowledged more troops are needed to secure the country ahead of elections in January, raising the prospect that the United States may have to enlarge its 140,000-member force.
Meanwhile, insurgent attacks across Iraq continued to claim its daily trickle of US casualties, as the US military announced another marine had been killed in clashes Wednesday in the restive western province of Al-Anbar.
More than 1,000 US soldiers and thousands of Iraqis have been killed since the US-led invasion in March 2003.
A US vehicle was also hit by a bomb in renewed clashes with radical Shiite militiamen in the Baghdad hotspot of Sadr City, leaving three soldiers wounded, witnesses and the military said.
Intense clashes also broke out in the rebel stronghold of Samarra, a city which the US military says is infested with foreign fighters, an AFP correspondent reported.
US troops had earlier sealed off the city and called in air strikes, killing three people, according to local police.