The German driver, along with his teammates in the #2 919 Hybrid, Romain Dumas and Neel Jani took the WEC drivers’ title on Saturday with a sixth-place finish in the season finale at Bahrain.

However, it is understood that Lieb has been informed by his employers that he will not be returning to defend his title with Porsche in 2017.

When asked about his future by Motorsport.com in Bahrain, Lieb refused to comment.

Nick Tandy and Andre Lotterer will both join the Weissach marque’s LMP1 roster next season, with Mark Webber’s retirement having already opened up one vacancy in the team. Jani, Timo Bernhard and Brendon Hartley are all expected to stay.

It remains to be seen whether Lieb, a works Porsche driver since 2003, will be offered a return to the manufacturer's GT ranks.

Dumas also vulnerable

There could yet be a further change in the Porsche LMP1 line-up in 2017, with Dumas also still believed to be in danger of losing his seat.

Were the Frenchman to lose out, 2015 Le Mans 24 Hours winner Earl Bamber remains the leading candidate to take his place, although it remains to be seen how Porsche would arrange its crews in such a scenario.

Dumas insisted he still has a valid contract, but did not specify he would be back in an LMP1 car next year, only saying he will have "something to do."

“We will see what will happen,” he told Motorsport.com in Bahrain. “I have two years left on my contract [with Porsche], so I will see what I will do.

"I will have something to do. I’m 39 next month, I won quite a lot of things, so I don’t have big problems right now.”

Meanwhile, speaking to Motorsport.com last weekend in Macau, Bamber said he had not yet been told whether he would be given the chance of a full-time LMP1 seat, but admitted it was his goal.

"I'm in if they want me,” said the New Zealander. “If they don't want me, they don't want me.

“Sure, I want to try and get back in the [LMP1] car. I won Le Mans in 2015, so it’s a big goal for me. But it's up to them if they put me in or not."

Additional reporting by Khodr Rawi and Stefan Ehlen