While the green light has been given on its return to IMSA competition next year, Porsche has yet to decide on the future of its factory GTE-Pro effort in the FIA World Endurance Championship.

Head of Porsche Motorsport Dr. Frank Steffen Walliser has denied recent reports that the Manthey squad won’t be back for a fourth consecutive season in the globe-trotting series, with the program still under evaluation.

“This is something that is not finally decided,” Walliser told Sportscar365. “It depends a little bit on the result and our general situation and the introduction of the new GT3-R. This is where we’re figuring out how it will work.”

The Porsche 911 RSR has struggled in WEC trim, with the team having been winless since Shanghai 2014, compared to the CORE autosport-run entries in the TUDOR United SportsCar Championship, which are the on heels of three straight class wins.

A Balance of Performance adjustment for this weekend’s Six Hours of Nürburgring sees the pair of GTE-Pro entries shed 10kg, with the GTE-Am cars getting a further 5kg weight break.

“In IMSA, it shows that it’s possible, with close racing,” Walliser said. “The FIA has also done some measures now. For me personally, I think it’s going in the right direction. We welcome this but we have to see how it will look in the race.”

Walliser said a final decision on its 2016 GT program will be decided in late October.

He admitted the Porsche-owned Manthey squad could end up fielding the new 911 GT3-R in some of the key endurance races next year.

“All of the discussion with the FIA has been fruitful and based on a partnership,” he said. “In general [the WEC] is a very good championship.

“If we made changes in the program it’s definitely within our internal situation and nothing against the championship.”

Should Porsche return to the GTE-Pro ranks, it would result in a four-way manufacturer battle, with Ford joining the existing Aston Martin and Ferrari squads with its Multimatic-built Ford GT.