Renault boss Cyril Abiteboul claims Formula 1 may only have "guidelines" to form the 2021 regulations by next month's deadline.

By the current system, an agreement must be reached on major changes 18 months in advance meaning the end of June is theoretically the date a deal must be signed.

However, with Liberty Media looking to rewrite many areas, including financial regulation through a budget cap, a new approach to revenue distribution and an overhaul of the sporting regs, negotiations have been very slow.

Recent speculation has suggested F1's owners could water down some of their bigger proposals to get an agreement in place, but even that likely won't be enough to meet the initial June deadline.

"Will we have a signed contract by FIA, Formula 1 and all 10 teams by end of June or mid-June for the World Motor Council? No, obviously no," Abiteboul said last weekend in Monaco.

"But in my opinion there has been a lot of groundwork already covered.

"I think it’s all about trying to agree what will be the key principles for 2021, from a commercial perspective, financial perspective, the key principles on the technical side and the sporting side.

"And in my opinion, we are probably 80% or 90% towards that point, that milestone.

"So with enough faith and enough goodwill from all participants and probably a bit of a push from the key stakeholders, there is no reason why something cannot be presented at the World Motor Sport Council that will be advanced enough to give useful guidelines for the remainder of the year, so that we have a complete set of guidelines for the end of the year."

Also Read:

• Red Bull: 2021 F1 talks 'like Brexit' but hope remains for a positive outcome
• Renault announce internal shake-up in effort to optimise 2021 performance
• Mixed messages from F1 bosses as 2021 talks reach key stage

It has already been suggested that the June date can be pushed back to October with unanimous agreement.

However, Williams deputy Claire Williams has warned any initial proposals put forward to the WMSC can't then be significantly altered when talks continue.

"We’re now at that point where we need to have that full set of regulations so that we can plan and prepare out businesses for that season," she explained.

"I’m sure there are going to be some further negotiations after that point. For a team in our position clearly, when it comes to the technical regulations we wouldn’t want too much movement after that.

"People are going to start working on those, people are already working, and we don’t need to be wasting resources with a huge change subsequent to the issuance of the first draft.

"I don’t think there’s much choice. We have to get those regulations out and so I believe it should be done and I’m sure it can be done."