BMW Sauber boss Mario Theissen has confirmed FOTA are keeping "all options open" as their row with the FIA rumbles on.

The peace agreement struck in Paris just over two weeks ago between FIA president Max Mosley, Formula One supremo Bernie Ecclestone and FOTA chairman Luca di Montezemolo has crumbled within the past two days.

The situation has not been helped by what Theissen has described as "irritating elements", arguably di Montezemolo for initally crowing in the wake of the £40million budget cap being scrapped, and Mosley for responding in a seemingly childish manner.

Although there is confidence the matter will be resolved within the next fortnight, whilst a degree of uncertainty remains, so does the threat of a breakaway series.

"All three parties are negotiating, almost permanently now, making slow but steady progress, but we are not there yet," said Theissen.

"We still don't have an agreement, so we cannot sit back and wait. We have to keep all options open, which means we have to look at other courses (of action) as well."

Referring specifically to a breakaway, Theissen added: "We are still looking into this.

"We did stop for a few days (after agreement was reached) until we recognised we were not where we thought we were.

"There are some irritating elements that rocked the boat again, and that applies to us as well, so you cannot really be sure where you are.

"If you look at the overall picture, then we have made significant progress.

"We might come to a conclusion, as the FIA indicate, within a few days, it might take a few weeks, or we might finally find out there is no agreement and we have to prepare for other possibilities."

Theissen, though, felt the FIA's claim a resolution would be found "in the coming days" was perhaps being optimistic.

The situation has become a clear one in that FOTA are refusing to sign a new Concorde Agreement - the confidential document that governs the commercial side of the sport - unless they have cast-iron assurances Mosley will not stand again for the presidency.

It has resulted in high-level talks taking place between the eight FOTA teams and senior figures above Ecclestone at CVC - the commercial rights holders - who are determined to protect their £1.5billion asset.

A breakaway series is ultimately being viewed as the last resort, as highlighted by Red Bull Racing team principal Christian Horner.

"The thing that was compelling after the breakaway was announced was the amount of support that was forthcoming, pushing the teams to say 'Yeah, you've done the right thing. Go ahead,'" commented Horner.

"Ultimately for Formula One, there does need to be a solution, and it does need to be the Formula One world championship.

"No one will benefit from a breakaway unless a solution genuinely cannot be found."

Toyota Motorsport president and FOTA vice-chairman John Howett was another to confirm a rivals series was still on the cards.

"It's still there, but we still have to act in a professional and sensible way," said Howett.

"I don't think we've ever taken it away. We've just put it on the backburner, although it is probably closer now than it was 24 hours ago.

"But we know exactly what we expect, what we need to get, and we are making positive progress."