The decision came after a joint news conference the pair held in Washington on Friday on the Middle East crisis, Blair will tell senior executives of Rupert Murdoch's News Corporation empire in Pebble Beach, California.

"I have not at all given up on the WTO trade round," Blair will say in the speech late Sunday, according to extracts of the speech released in advance by his office.

"After a long discussion with President Bush after our press conference Friday, we both agreed we needed to make one final effort to re-energise the negotiation and I hope we can do so within the next few weeks."

Blair made the comments but did not expand on details as he touched on one of his pet themes, globalisation and the interdependence of countries and policy making.

WTO chief Pascal Lamy suspended the troubled Doha round of trade talks on removing trade barriers last Monday because of a failure by six major trading powers to compromise on tariffs and subsidies, especially in agriculture.

TRADE TALKS STILL 'DIFFICULT BUT DOABLE': MANDELSON

Another report from London adds: Negotiations on a global free trade deal can still be salvaged after the collapse of World Trade Organization talks last week, the European Union's trade commissioner, Peter Mandelson wrote in Monday's edition of the Financial Times.

Agricultural reforms being demanded of the EU are "difficult but doable" and cuts in farm subsidies in the United States would be "politically hard with mid-term elections in November, but not impossible," Mandelson wrote.

He said that the so-called Doha Round of trade talks are "losing the race against time", and discussions "cannot now be concluded by the end of 2006".

But, he added, "the costs of no agreement are far greater than the inconveniences of a less than perfect one."

"A failure of Doha would strengthen those who want to turn their backs on globalization and retreat into protectionism."

Major powers, particularly the United States and EU, have bitterly traded blame for the collapse of talks, each accusing the other of inflexibility over aid to farmers.

The Doha Round, which opened in the Qatari capital in 2001, was aimed at removing agricultural and industrial trade barriers, and using commerce to give developing countries a boost. It was meant to yield a trade treaty by the end of 2004, but the target was later shifted to December 2006.