Fernando Alonso hasn't ruled out moving to Williams next season as the Spaniard prepares to decide whether or not to stay at McLaren for 2018.
The Spaniard, who has spent three fruitless seasons on the McLaren-Honda 'project' since his switch from Ferrari, is out of contract at the end of the season.
Having previously said he would seek a 'winning' drive in 2018 in an apparent signal he was preparing to depart, Alonso has subsequently seen the door close on him at Ferrari and Red Bull, both of whom have opted against changing their line-ups for next season, while Mercedes are set to announce Valtteri Bottas will stay alongside Lewis Hamilton.
Much is likely to depend on McLaren's own looming decision on their power supply for 2018 with team boss Zak Brown indicating Honda need to make a 'drastic' improvement between now and the rest of the season if Alonso is to be persuaded to stay.
Renault would surely welcome back Alonso if the two-time world champion opts to leave while Williams are rumoured to have offered Alonso a seat for next year.
"I will have a think and take decisions in the next month," said Alonso when asked about the Williams speculation.
"I have had offers. I have had offers in June, July and August. 60 per cent of them I have said no to already, the other 40 per cent is still on the table."
McLaren: Honda must convince Alonso
In an apparent indication that his decision will be based on McLaren's choice of power provider, Alonso added: "I will wait for as long as possible to have better and clearer ideas and projects.
"I haven't thought about my decision yet. I will wait and make the best decision for me and the one which makes me happier next year."
An 'easy' one-two for McLaren on car performance?
At the culmination of Qualy Two at Spa, Alonso was heard voicing his frustrations over team radio, shouting "no power" as he failed to reach the top-10 shootout.
But afterwards the Spaniard was at pains to insist the McLaren car had impressed and would have achieved a comfortable one-two but for the crippling lack of power from their Honda engine.
"We know what the deficit is at this circuit on power. When we were 1.5 seconds off P1 in Q2, that means an easy one-two for us. The car was performing extremely well this weekend so it was very positive.
"In Q2 the engine didn't perform and l had to abort the lap because l had no power. We were more competitive than expected. McLaren showed something special today."
Pressed on whether his patience had snapped when his engine failed, Alonso countered: "The situation didn't change today. The last three years have been more or less the same: we lack power and a little bit reliability.
"We keep trusting that everything is going to get better, hopefully soon."