Richard Lugar, a Republican senator, urged President George W. Bush to do some "real truth-telling" to explain to his people how much commitment and money would be needed to rebuild the country.
His Democrat colleague Joseph Biden added that the US is likely to be in Iraq "in a big way with forces and economic input for a minimum of three to five years".
An Iraqi oil ministry official said the latest blast occurred near the border with Syria. US occupation forces said they were checking the report
"An explosion took place in the oil pipeline near the Syrian
border at 1:00 am (2100 GMT Sunday) last night," said the official, who refused to be named.
The explosion occurred two days after an explosion struck a gas pipeline near Baghdad that oil ministry officials said was an “act of sabotage”.
Iraq was pumping around 200,000 barrels a day to Syria at
favourable prices before the US-led war that began on 20 March.
US-led invading forces bombed the pipeline during the war to stop exports.
The line is separate from Iraq's main export pipeline, running from the northern Kirkuk fields through Ceyhan on Turkey's Mediterranean coast.
Payments for former soldiers
Meanwhile, US occupation authorities had decided to give payments to former Iraqi soldiers starting from 14 July, the occupation forces said on Monday.
“The payments will be paid monthly and the recipients must renounce Baathism and violence”, a statement said. Payments would range from US $50 to $250. Between 200,000 and 250,000 former soldiers would be eligible for the payments.
An ultimatum by the former soldiers given to the occupation forces was to expire on Monday.
They had threatened military action if they were not paid.
“We are all very well trained soldiers and we are armed. We will start ambushes, bombings and even suicide bombings”, said Tahseen Ali Hussein, a former soldier.
“If on Monday at noon, the Americans do not find a suitable solution to our tragic situation, we will take up arms”, he told AFP on Thursday.
A number of Syrian border guards were wounded when US special forces in Iraq attacked a convoy of suspected high-profile members of Saddam Hussein's toppled government, US officials said on Monday.
"It's not clear how they were injured, whether they were caught in a crossfire or what. But we are, I believe, still treating three of them," said one official.
Syria, which has had often tense relations with Washington over US charges that it supports terrorism, said it had no comment even as Washington said there had been no official government contact with Damascus over the incident.
The US official, speaking on condition of anonymity, said the attack occurred last Wednesday in a "fairly remote" area near Iraq's western city of Qaim close to the Syrian border.
US officials did not say whether their forces, backed by aircraft, crossed into Syria and were vague on how Syrian guards were involved. The convoy was apparently attempting to escape into Syria, the officials said.
The officials said there was no indication Saddam or his two sons Qusay and Uday were killed in the attack. Investigators had not yet determined the identities of those killed, the officials said.
Leading Shia cleric Ayatollah Ali Sistani, in the meantime, has expressed “great unease” over the US occupation.
The Washington Post reported that the cleric wanted the US to allow Iraqis to rule themselves.
“We see that it is necessary that they should make room for Iraqis to rule themselves by themselves without foreign intervention”, Sistani said from his home in the southern city of Najaf.
The ayatollah, who - unlike many Shia clerics - remained in Iraq throughout the former regime's rule, told the newspaper that the biggest threat facing the country was “obliteration of its cultural identity”.