Mercedes F1 chief Toto Wolff says he would welcome Porsche to Formula 1 and reckons the fellow German marque is "interested" given their involvement in shaping the 2021 rules package.
Porsche recently quit the WEC to join Formula E but has been actively involved in shaping the new 2021 F1 regulations by FIA invitation amongst other manufacturers both currently involved and not.
Although a Porsche works team looks unlikely, the manufacturer could be looking at supplying engines in the future with a link-up with Red Bull or Williams rumoured.
Wolff however is keen for more competition and says Porsche would be welcomed.
"The more we can fight, on our little playground – in the sandpit – the more we enjoy it," he told Sky Sports F1.
"I guess that Porsche is interested, and looking at the environment, it's not quite clear how [they would become involved]. They are sitting on the table and giving their input [into the rules]."
The new regulations are due to be rubber-stamped in the coming weeks and Wolff, like everyone, is keen to see what's been decided.
"They are not cast in stone, but I guess next week in the Strategy Group we are going to hear a little bit more.
"It's still not agreed between what's been on the table in the past sessions and all of the engine manufacturers. So there are quite some tough discussions ahead, I guess.
"For us it's important that the technology message is still there, in efficiency. Because efficiency is important when the whole world moves into green and electricity, and we, for historic nostalgia, move 20 years back – it's not something that we want to do."
He added: "I think transparency and a clear path are important, we need to know what's happening in 2021, what the regs look like, on the power unit side and on the chassis side, in order to get things moving and avoid a cost escalation, a cost rush, at the last minute.
"I hope that with next week's meeting we have a little more understanding and input, and then we'll see how it ends up."
