Niki Lauda has hit out at F1 supremo Bernie Ecclestone, insisting that his recent comments about Nico Rosberg are "very unfair".

As Rosberg closes in on his first title, Ecclestone said that he would prefer if Lewis Hamilton won a third consecutive crown because "there is nothing to write about" Mercedes's German driver.

Mercedes team chairman Lauda hit out at Ecclestone's comments in conversation with the German newspaper Bild am Sonntag.

"This criticism of the possible world champion Nico Rosberg is quite excessive," Lauda said.

"And especially at such a crucial stage of the world championship, I think it's very unfair."

Mercedes team boss Toto Wolff also backed Rosberg in the wake of Ecclestone's comments.

"I think the driver who should be champion is the one at the end of the season with the most points.

"He deserves the title and should be fully appreciated."

The season continues today with the United States Grand Prix in Austin.