Competing in the Indianapolis 500 is enticing to Formula One stars Fernando Alonso and Sebastian Vettel because of its status as one of the greatest races in motorsports, and both aren't ruling out a future drive.

"There are three races in the world are very attractive: Indy 500, 24 Hours of Le Mans, and the Monte Carlo Grand Prix in Monaco," said Alonso, the 2005 and '06 World Champion.

The 100th Running of the Indianapolis 500 Mile Race is May 29, 2016, but because of their racing commitments that would likely be too soon.

Vettel said he's intrigued about racing on the 2.5-mile oval if not next year than in the near future, but would need to take measures to prepare.

"Just jumping in and doing a good job, oval racing is very different to racing in Formula One,” he said.