LONDON - Rubens Barrichello's Formula 1 future looks increasingly uncertain after a major Williams shareholder said the team was talking to 2007 champion Kimi Raikkonen about a possible comeback.Austrian Christian 'Toto' Wolff told the Kronen Zeitung that the Finn, who won his title with Ferrari, was one of several names on their list of possible drivers for next season."We are in conversation with Raikkonen," he said, "but he is only one of several options."Former champions Williams, enduring their worst season in F1 with five points from 17 races, has said nothing officially about any contacts with the 32-year-old 'Iceman' despite growing news media speculation.POPULAR FINNAsked at the recent Indian F1 GP whether Raikkonen might return to race for Williams next year, team chairman Adam Parr refused to be drawn."Our race drivers are Pastor Maldonado and Rubens Barrichello and if, and when, that changes we will make an appropriate announcement," he said.Raikkonen, still hugely popular with F1 fans despite having left the sport for World Rally competition at the end of 2009, told the latest edition of F1 Racing magazine that anything was possible but nothing had been decided. "There are many options and a lot of speculation," he said. "Until something is certain, there is no point in speculating because it could go any way. To be honest, I don't know myself yet."Barrichello, 39, who has started more races than any driver in the history of F1, has said he wants to keep racing and is expecting a decision on his future before his home season-ending Brazilian GP on November 27, 2011."The fans need to know. Williams told me they would like to make a decision before Brazil, so I hope at least that is a positive," Barrichello said recently. "I would like that to happen."Rookie Maldonado brings substantial sponsorship to the team from the Venezuelan state oil company and is sure to stay.BIG DECISIONAdrian Sutil is likely to be another strong option for Williams if the experienced German is not retained by Force India, whose principal Vijay Mallya said in India that he hoped to name his 2012 drivers before this weekend's race in Abu Dhabi but that looked less likely on Monday."All the drivers have asked me to make an early decision, and I respect that," he said in a team preview. "I have a big decision to make - but it's not made yet."Britain's Paul di Resta is expected to stay with the team, with Germany's Nico Hulkenberg, who raced for Williams in 2010 and took pole position in Brazil, widely tipped to join him at Sutil's expense.The other big question in the drivers' market hangs over Renault, with Robert Kubica's return still up in the air. The Pole has yet to step into an F1 car since his near-fatal pre-season rally crash and Renault will be trying out Frenchman Romain Grosjean in Friday practice this week.Brazilian Bruno Senna, who has a contract to stand in until the end of the season, is also hoping to stay on if Kubica cannot return.The top four teams' - Red Bull, McLaren, Ferrari and Mercedes - drivers will be unchanged for 2012.