Suzuki, which 'suspended' its MotoGP activities at the end of 2011 due to the financial crisis, is still working towards a 2014 return.

Since bowing out, Suzuki's MotoGP intentions have been kept alive by reports of track tests for the new 1000cc bike, interest in riders such as Cal Crutchlow and the reported signing of Aspar's Randy de Puniet as a test rider.

The latest Suzuki signal is from Dorna boss Carmelo Ezpeleta, who told BBC Sport: "They [Suzuki] are asking us to have some testing during the 2013 season and if everything goes well maybe we will see them in 2014."

But while a fourth official MotoGP manufacturer would doubtless be welcome, Ezpeleta added that his main priority is to brighten up the racing.

"We have three manufacturers at the moment in Honda, Yamaha and Ducati. If Suzuki are in we have four, and that would be the same as [the number of engine suppliers in] Formula 1, so it is not a big problem," he said.

"The main thing is to have more competitive races. If we can do that with more manufacturers than all the better, but having competitive bikes is the key."

A control ECU will be introduced for the 2014 MotoGP season, although the maufacturers will still be allowed to use their own software.

Suzuki last won the premier-class title with Kenny Roberts Jr in 2000, but took just one race win - with Chris Vermeulen at a wet Le Mans in 2007 - after the start of the four-stroke era in 2002.

Suzuki's 500cc World Champions:
Barry Sheene (1976 and 1977)
Marco Lucchinelli (1981)
Franco Uncini (1982)
Kevin Schwantz (1993)
Kenny Roberts Jr (2000)