The world of F1 is in Paris on Thursday for a crisis meeting about the 2021 rules.

The draft regulations began to do the rounds last weekend in Montreal, but it quickly emerged that the teams are still hopelessly split.

For instance, even the rule banning tyre blankets is being opposed, with many saying it will not be workable.

"Of course it's workable," Alfa Romeo team manager Beat Zehnder told Auto Motor und Sport.

"The DTM has shown that the races without the blankets are even better," he said. "It's also cheaper. We will save EUR 300,000 in freight costs every year, and every four years we need to spend EUR 750,000 on new blankets."

Also controversial is Liberty Media's proposed US $175 million annual budget cap, with many teams saying the number is much too high.

"We had to compromise for the beginning," said Liberty sporting boss Ross Brawn.

"With that number, the system will not be under stress and we can develop. If a crisis comes, we can reduce the limit.

"We have a foot in the door now, and that was important," he added.

Thursday's meeting will take place at the FIA headquarters in Place de la Concorde.