Great Britain and Malaysia's places on the MotoGP calendar for 2017 remain "subject to contract" after the provisional race list was released on Wednesday.
The championship includes the same meets as in 2016, with proposed races in Indonesia and Thailand not making the cut in time for next season.
Qatar will again by the first of the 18 races, with Valencia hosting the season finale in the first of a new five-year contract signed earlier this week.
A two-week break between the Argentinian and United States Grands Prix has been introduced, while there will only be seven days between Mugello and Barcelona in June.
However, Britain's grand prix in late August and the penultimate race in Sepang have yet to be confirmed, with MotoGP organisers stating their contracts had yet to be agreed.
The current 18 venues will be joined by Finland in 2018 when the currently under construction Kymi Ring joins the calendar, while Thailand and Indonesia could also be involved.