Apr.21 (GMM) The next test to feature Bridgestone's developments of the intended 2009 slick tyres is scheduled for July.

F1's official sole tyre supplier said in a statement that it expects to make even "more progress" with the compounds, following the major test with slicks at Barcelona's Circuit de Catalunya last week.

The first slick test was at Jerez last December.

Teams tried three revised slick compounds at the recent Barcelona session - nine sets allocated to each team - and technical manager Tetsuro Kobayashi said he was happy with the results.

He also responded to some drivers' concerns about the scheduled banning of tyre blankets next year by saying the warm-up situation out of the pits was "much improved".

Meanwhile, Ferrari designer Nicholas Tombazis ruled out speculation that the Italian team is planning to roll out a "prototype" of its 2009 car at the next slick test.

"Totally implausible," he said in the pages of La Gazzetta dello Sport.