Only two teams are still holding out for a supply of Michelin tyres for the 2011 season.
It has been reported in recent days that an announcement about Pirelli becoming the sport's new tyre supplier is imminent.
Bernie Ecclestone said on Friday that he hopes the situation is clearer by the end of this Turkish grand prix weekend.
Germany's Auto Motor und Sport claims that ten of the 12 teams are clearly in favour of Pirelli's proposal.
Some time ago, Ferrari, McLaren, Renault and Mercedes were voting for Michelin.
But Mercedes and McLaren have since switched camps, meaning that if a poll was held today, only Ferrari and Renault would still be holding out for the French marque.
"I think we are getting there. We are getting organised now," F1 chief executive Ecclestone told reporters in the Istanbul media centre on Friday.
