In a move which is likely to go down like a lead balloon with his current employers, Juan Pablo Montoya has said that Jenson Button's decision to join WilliamsF1 for 2005 - should the move happen - is "crazy".

"Maybe there's something at BAR he doesn't like or something," the Colombian told reporters at the Hungaroring today, "but the whole team was built around him.

"I think it's crazy," he continued, "but it's his choice. Probably Williams can turn it around, but they got it completely wrong this year."

Montoya heads to McLaren for 2005, while teammate Ralf Schumacher is Toyota-bound. The radical looking WilliamsF1 FW26 has proved to be a major disappointment, so much so that the team is adopting a more conventional front for the remaining six races.

Sam Michael has said that the FW27 will be better, but Montoya is not convinced and believes next year's BAR will be better.

"BAR's results were getting better," he said. "In the last race, he had a 10-place penalty and finished second. After that, how your mind goes to go somewhere else I don't know. Williams have to come a long way. They proved last year it can be done and this year will maybe help them do so because they got it completely wrong."

The Colombian who has had an 'interesting' couple of seasons alongside Ralf Schumacher, also wonders how Button fare with Mark Webber, as the Grove outfit continues its tradition of refusing to nominate a number one driver.

"It will be interesting to see what happens between Jenson and Mark," he said. "Webber being Australian and Sam Michael being Australian, you know."