Formula One Group chief executive Bernie Ecclestone has described Fernando Alonso's crash during pre-season testing in Barcelona as "completely inexplicable".

The Spaniard hit the wall on the exit of the 150mph Turn Three at the Circuit de Barcelona-Catalunya on February 22 and spent three days in hospital after suffering concussion.

"What has surprised me is what happened [in Barcelona]. It is completely inexplicable, for him as well," Ecclestone is quoted by DPA as saying. "Fernando is a little surprised by what has happened to him.

"McLaren doesn't want to discuss it, so there's not much we can do. It is really a sporting issue. So maybe it is one of those things that is necessary for the FIA to investigate."

Alonso will not take part in the opening grand prix of the season in Australia following advice from doctors.