W Series will support Formula 1 at this year's United States and Mexican grands prix as it adds an additional two rounds to the 2020 season calendar. 

A six-round calendar had previously been confirmed but W Series has secured a further two races which will take place on grand prix weekends in Texas between 23-25 October and Mexico City on October 31-November 1, taking its sophomore campaign up to eight events in total. 

The US and Mexican rounds will conclude the 2020 W Series schedule, following races in Russia, Sweden, Italy, Germany, Britain and the Netherlands, all supporting the DTM. 

It marks a huge milestone for W Series, which enjoyed a successful inaugural season in 2019 when it launched as the world's first female-only single-seater championship. 

F1 managing director, Ross Brawn, said: “We are delighted to welcome W Series to two such spectacular events of the 2020 FIA Formula 1 world championship such as those in Austin and Mexico City.

"In just one year, W Series has contributed significantly to increasing interest in the topic of diversity and inclusion in motorsport. We are convinced that our sport must offer equal opportunities for men and women to compete together - it is no coincidence that improving the diversity of the F1 grid by supporting and promoting driver talent from underrepresented backgrounds is one of our strategic objectives.

"The ability for the great crowds who traditionally attend the Austin and Mexico City Grands Prix to see these talented female drivers up close will definitely further raise the awareness of the importance of inclusion and diversity in motorsport."

W Series CEO Catherine Bond Muir said the deal with F1 reflects growing interest in the series. 

"We at W Series are absolutely delighted that, in only our second season, our championship has been welcomed by Formula 1, and we're utterly thrilled that the final two races of the 2020 W Series season will therefore take place as part of the Formula 1 platform," she explained.

"Our two all-new races will follow six races on the DTM platform, making a very varied, extremely exciting and truly international eight-race championship, in eight countries across the globe.

"I'm particularly pleased that W Series will now stage races outside Europe, and the USA and Mexico are of course both very important new territories for us.

"Interest in and enthusiasm for W Series was enormous in our first season, 2019, among media and fans alike, and the addition of two all-new W Series races on the Formula 1 platform will inevitably increase that enthusiasm and interest.

"A lot of work has gone into stitching the W Series-Formula 1 deal together, but above all I want to thank W Series' drivers, the brave and talented young women who captured the imagination of the sporting world last summer.

"Mark my words: they'll do so again this year, from May to October, all over the world."

Williams F1 development driver Jamie Chadwick will return to the championship this year in a bid to defend her W Series crown.