The pledge by Alastair Campbell, Blair's influentual director of communications and strategy, came amid controversy over the way that Downing Street handled spy data in the run-up to war on Iraq.

A spokesman for Blair's office said Campbell spoke to intelligence chiefs in the wake of a February dossier on the way Saddam Hussein's regime was trying to hide its illegal weapons programs.

Parts of the dossier turned out to have been lifted from the Internet -- complete with typographical errors -- from a university thesis written by a US student 12 years earlier.

"Alastair Campbell spoke to those who had been responsible for its production to demand tighter procedures," the spokesman said.

"He also assured the (intelligence) agencies that far greater care would be taken in dealing with anything that might impact on their reputation or their work."

The spokesman added that Campbell was "on excellent terms" with Sir Richard Dearlove, head of the Secret Intelligence Service, or MI6, Britain's overseas spy agency.

He denied a report in the Sunday Telegraph newspaper that Campbell -- a former tabloid journalist known as Downing Street's chief "spin doctor" -- had, in effect, apologized in writing for the so-called "dodgy dossier."

"Like many other stories on weapons of mass destruction, this one is totally overblown," he said.

Blair has vigorously denied claims that Downing Street had embellished another dossier on Iraq and weapons of mass destruction, published in September, to beef up the case for war.

Unnamed sources told BBC radio that a line in that document -- that Iraq could deploy chemical or biological weapons in just 45 minutes -- was inserted at Downing Street's behest over the reservations of spy chiefs.

In a bid to quell the controversy, Blair announced Wednesday an investigation by the British parliament's intelligence and security committee, with its findings to be made public.

WAR.WIRE