At Spa, Spaniard Alonso seems out of patience for Honda, who have struggled since day one of the works McLaren project.
"The current situation didn't arise in a single day -- it's been three years," he said.
As for the new Williams rumour specifically, Alonso said: "I have received some offers -- in June, July and in August. 60 per cent of them I have already rejected.
"The other 40pc are still open," he added.
And a similar non-denial is also coming out of the Williams camp.
"We have not yet announced who will be driving for us next year," said technical boss and co-owner Paddy Lowe.
"It's something we're working on so I can't confirm or exclude anything."
And deputy boss Claire Williams told Brazil's Globo: "It would be great for any team to have Fernando.
"But as I've said, we are focusing on this year. Maybe the drivers will be something to worry about towards the end of the year.
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