Bernie Ecclestone believes Mercedes were prepared to offer Red Bull a supply of engines for 2016. Bernie Ecclestone believes Mercedes were prepared to offer Red Bull a supply of engines for 2016.

Bernie Ecclestone has told Sky Sports News HQ he believes Mercedes were prepared to offer rivals Red Bull a supply of engines for 2016.

According to the F1 ringmaster, the world champions had second thoughts after a handshake agreement was made between Mercedes executive Niki Lauda, and Dietrich Mateschitz, the Red Bull owner.

"I thought and was told that Mr Lauda had made an agreement with Mr Mateschitz and they had a nice handshake when Niki confirmed they would be supplied with Mercedes engines," Ecclestone told Sky Sports News HQ.

But according to Lauda, the agreement only collapsed because Red Bull failed to follow up their initial approach.

"Christian [Horner] and Helmut [Marko] wrote us one letter to say they would like engines. I said 'yes, but first we have to discuss with Mr Mateschitz' because Mateschitz, for whatever reason, never liked Mercedes," Lauda told Sky Sports F1.

"There is something in the past which I do not know. So I went to see Mateschitz myself because I know him and asked 'are you really interested?' and he said 'yes, but, but, but...' And then out of this 'but, but, but' we never continued any talks."

Niki Lauda, non-executive chairman of Mercedes GP walks with Red Bull Team Principal Christian Horner

The claim and counter-claim verbal sparring has become an unedifying backdrop to mounting concern that Red Bull, adamant they will not continue in F1 unless they source a competitive supply of engines, will carry out their threat and leave F1 at the end of the season.

"The current situation is quite critical because as we sit here, we don't have an engine," team boss Horner said after the Japanese GP on Sunday.

After Mercedes formally rejected Red Bull's request for engines - first made at the British GP in July, two months before the team served 'divorce papers' on their current suppliers, Renault - the former world champions have entered talks with Ferrari, the other leading engine manufacturers on the grid.

However, Ferrari have apparently indicated that they will only supply Red Bull with their 2015 engines next year.

"I understand they are being offered engines that are currently in use today and not the engines which will be used [by Ferrari] in 2016," said Ecclestone.

Red Bull have demanded parity with Helmut Marko, the team's advisor, reportedly accusing Ferrari of 'playing games' during the ongoing negotiations.

With the clock ticking on a deal to be completed, the cars of both Ferrari and Mercedes were only fleetingly seen during the official race broadcast of Sunday's Japanese GP despite Lewis Hamilton beating his Silver Arrows' team-mate Nico Rosberg and the Scuderia's Sebastian Vettel to victory. 'Mr Ecclestone has his ways of reminding people who's in charge from time to time, and this may have been one of them,' wrote Martin Brundle in his latest column for Sky Sports.

Renault, meanwhile, have moved a step closer to remaining in the sports as a fully-fledged 'works outfit' by signing a letter of intent to buy Lotus.

Don't miss this the F1 Midweek Report for analysis of the Japanese GP. Natalie Pinkham is joined by David Brabham and Ted Kravitz on Wednesday at 8:30pm on Sky Sports F1.