BAGHDAD, Aug 5: US and Iraqi troops backed by American fighter planes attacked guerillas in western Iraq on Friday, launching the latest in a series of offensives in the volatile Euphrates river valley since May. Iraqi Prime Minister Ibrahim Jaafari travelled to Najaf to consult the nation’s top Shia leader, Ayatollah Ali al Sistani, on the new constitution, which is due to be presented to parliament in 10 days.

Ayatollah Sistani’s support may determine the success of the document. The military operation, dubbed Quick Strike, comes two days after 14 US Marines were killed in a roadside bomb blast near the western town of Haditha, one of the deadliest attacks against US forces since the invasion began.

The blast, which brought the number of US troops to have died in Iraq to 1,820, has raised questions about whether Washington has underestimated the strength of the resistance.

More than 20 US troops have died in western Iraq this month. The new offensive, involving 1,000 troops, began Wednesday and is focused on the Haditha area, but was not launched in response to the roadside bomb attack, a military spokesman said.

“The objectives are to interdict and disrupt the insurgents and foreign terrorists in Haditha, Haqlaniya and the Barwanah area,” Lt Col Steve Boylan said.

The Euphrates valley, which runs northwest from Baghdad to the Syrian border, has become one of the most violent regions of the country and a heartland of the resistance. US commanders allege the valley, thick with palm groves, riverside marshes and old settlements, is a conduit for guerillas and weapons entering Iraq from Syria. Its topography makes it difficult for conventional forces to operate.

Beginning in May, the Marines have launched successive offensives in the area, including in towns along the border and villages near Haditha, but guerilla attacks have persisted.

Often, when US forces arrive in a suspected guerilla stronghold they discover that fighters have melted away. Once US troops leave, the fighters return, residents say. Hospital sources in Haditha said at least three Iraqis had died in fighting on Friday. There was no word on any US military casualties.

MEETING WITH SISTANI: Prime Minister Ibrahim Jaafari’s meeting with Ayatollah Sistani at the latter’s home in Najaf comes at a crucial time in Iraq’s political process. A draft of the constitution is due by Aug 15, but widespread differences remain among the group charged with writing it.