Fernando Alonso on Thursday refused to categorically rule out leaving current team Ferrari as soon as next season for either former outfit McLaren or reigning champions Red Bull.
"This is a very difficult question to answer... I will do the best for Ferrari," Alonso told reporters ahead of the Japanese Grand Prix, when asked to clearly state that he would not be driving a Red Bull or a McLaren next season or in 2016.
"You question, I answer. You cannot do the question and answer for me," the Spaniard, when pressed further on the matter, jokingly added.
Alonso's contract with Ferrari runs until the end of the 2016 season, but the 33-year-old's future has been a regular topic of paddock discussion.
The Spaniard, currently driving in his fifth season with Ferrari, has grown increasingly frustrated with the lack of success for the sport's glamour team which hasn't won a race in over a year and faces the prospect of recording its first winless season since 1993.
Speculation surrounding his future has been rife this year, a season that has seen a number of key management changes at Ferrari, with long-serving president Luca di Montezemolo the latest to announce his departure.
Talk that Alonso's future lies away from Maranello has only grown louder in recent weeks and though refusing to rule out the possibility, the Spaniard on Thursday did say that the interests of Ferrari -- locked in a battle for third in the constructors' championship -- took priority over his future.
"As I said in Singapore, we are in the middle of a fight with Williams in the constructors' championship and I would like to help Ferrari to the maximum," said Alonso, who a fortnight ago in Singapore had expressed his displeasure over the rumours which he said were damaging team unity.
"This is the first priority for me -- on the track side to help the team -- and my second priority will be my future if there is anything to talk about."
Alonso has most strongly been linked with a move to either Red Bull or McLaren.
McLaren are set to switch to Honda engines from next season and the Japanese marque is understood to be particularly keen on getting their hands on a driver of Alonso's calibre.
Both the team's current drivers, 2009 world champion Jenson Button and rookie Kevin Magnussen, are out of contract at the end of the season and neither have been confirmed by McLaren for next season so far.
When quizzed about his chances of staying with McLaren next season, Button was coy. "I... I don't know," the Briton, who has been with McLaren since 2010, said.
"As you know I can't discuss anything to do with the contract," he said, before adding that McLaren was his "best option" for staying in Formula One.
Reigning world champion Sebastian Vettel, yet to win in what has been a difficult title-defence year for the German, also played down rumours of a seat-swap with Alonso.
"Well, I think there has always been rumours over the last couple of years, especially around this time of the season," the 27-year-old said.
"It's not really in my head. As I said, coming from the back at Singapore we made some progress and I hope that we can carry that momentum into this race and that's really where the focus lies."
Image: Fernando Alonso of Spain and Ferrari walks across the paddock ahead of the Japanese Formula One Grand Prix at Suzuka Circuit in Japan on Thursday
Photograph: Clive Mason/Getty Images