Australia's cricketers have been warned this summer's Ashes series could be scrapped even if a new pay deal is tentatively reached with the game's governing body.

In an explosive email from Australian Cricketers Association chief Alistair Nicholson to players on Saturday, he has warned the iconic Test series against England, due to begin in Brisbane on November 23, is under threat.

Negotiations over a new memorandum of understanding between players, led by Nicholson, and CA have all but broken down, although Fairfax Media can also reveal an emergency meeting between Nicholson and CA counterpart James Sutherland has been slated for Sunday.

In the email, Nicholson states: "If there is agreement, the next step would be the more intensive MOU and contract drafting period. Given past experience and the massive detail involved, this would take some time and still may not be completed with time enough to meet the needs of fans, sponsors and broadcasters invested in the upcoming tours and the summer of cricket.

"I add that it is hard to conceive of any further flexibility the players could possibly offer in these negotiations."

Cricket Australia said it was surprised and perplexed by the ACA's claims but would not comment on key details.

Australia's next series is a Test tour of Bangladesh in August. While the Ashes are almost four months away, much preparation, including broadcast inventory and sponsorship and advertising deals, must be locked in far earlier.

Amid the uncertainty, the England and Wales Cricket Board will also need to be assured the series will go ahead before Joe Root's team is allowed to leave home shores.

The complex MOU is likely to be 700-page document. The players remain frustrated at CA's response to what has been a "terms sheet" the ACA had developed during discussions with CA over the past fortnight. CA is said to have provided a "marked up" response via email on Thursday, questioning, if not rejecting, the players' revenue-model scheme and adjustment ledger and grassroots plans.

Players had thought the two parties had reached common ground since Sutherland finally joined negotiations a fortnight ago after much hankering from the ACA. Discussions had largely been left in the hands of experienced administrator Kevin Roberts. 

CA, however, has claimed the ACA's terms sheet has suggested players are paid more and less money should go to grassroots. The ACA rejected that claim when contacted by Fairfax Media.

CA officials are of the belief the ACA had thought CA would ignore the terms sheet and cease talks; instead CA said it would immediately debate the upgraded plans with the ACA. When CA began to point out what it claims were errors in thinking, the ACA is said to have lost patience.

"Contrary to this progress and ACA's attempts to resolve the dispute, on Thursday night the ACA received draft legal wording removing any reference to 'revenue share' in a proposed new Article 5 of the next MOU," Nicholson said.

"This was unexpected. It has setback negotiations and thwarted the prospects of agreement. The ACA will seek clarification on this as a matter of priority, as it seems to ignore a number of our proposed solutions in the terms sheet." 

Players have been paid from a gross revenue scheme since 1997; CA wants this to change to a set pool of money with a share in surplus funds. At stake in the new deal is about $450 million of payments due to players over the next five years.

Nicholson said the players had offered to modernise the revenue scheme and would contribute $30 million to grassroots and club cricket.

"We therefore offered a modernised model including the making of substantial concessions by the players in good faith. Namely, that players would accept a formal mechanism for redistributing amounts of revenue from the players to grassroots cricket via a new Players Grassroots Investment Fund (PGIF)," he said.

"Dependent on the achievement of revenue forecasts, we have proposed that this would be approximately $30 million injection from all male, female, international and domestic players. It is a show of the players' respect for growing the game and the next generation of players."

He also outlined the players' solution to end the nine-month impasse. This involved players accepting CA's revenue scenario forecasts, players accepting an agreed percentage of Australian cricket revenue, which factors in women players for the first time, and "revenue sharing is then modernised so that the players allocate an amount of the players share of revenue to grassroots investment. This could be up to $30 million via their PGIF fund".

"This figure has been arrived at as it would match the current offer from CA to direct its proposed administrative cost savings into grassroots cricket, which itself is a welcome contribution from CA," Nicholson wrote.

"Both parties agree to a gender-neutral pay model and the inclusion of women in the one MOU; and back pay be provided to players (who have kept training even though unemployed) and the current adjustment ledger would not be 'rolled over', both of which are, as instructed by you, plainly and rightly non-negotiable".

Players are fighting to be paid the $29 million of surplus funds they are owed under the current MOU as part of the adjustment ledger fund. CA wants some of this money to be parlayed into a new deal.

More than 200 cricketers have been unemployed since July 1. CA has saved $2 million in wages, with this money redirected to grassroots and club level.

The ACA has sought guidance from former Labor politician and chief unionist Greg Combet through the increasingly ugly spat.

WHAT'S UNDER THREAT:

* Australia's Test tour of Bangladesh in August

* A one-day series in India in October

* Women's and men's Ashes series

Men's Ashes series:

* First Test: Gabba, November 23-27 

* Second Test: Adelaide Oval, December 2-6 (Day-Night) 

* Third Test: Perth TBC, December 14-18 

* Fourth Test: MCG, December 26-30 

* Fifth Test: SCG, January 4-8 (Pink Test)