US president, George W Bush has started his European tour with a frank admission of trans-Atlantic divisions.

Arriving in Madrid yesterday Bush said: "I refuse to let any issue isolate America from Europe because Europe is too important to America's future. Sure there's going to be differences of opinion on big issues, but that will not prevent our friendship from enduring and growing stronger."

Despite Bush's "charm offensive" EU leaders had earlier rejected promises to boost research into global warming arguing that the US should instead abide by the 1997 Kyoto Accords.

France and Germany have restated their opposition to Bush's missile defence system ahead of a NATO summit today.