The United Cup, a new $15m (£13.5m) mixed team event that carries rankings points, will open the 2023 tennis season in Australia.

The new tournament will launch on 29 December and conclude on 8 January, eight days before the Australian Open.

It will replace the short-lived ATP Cup, a men's team event which ran for three years between 2020 and 2022.

The ATP Cup, which struggled to attract large crowds because of the Covid pandemic, replaced the mixed team Hopman Cup, which was staged every January for 30 years until 2019.

"The United Cup is an important and strategic collaboration between the WTA, the ATP and Tennis Australia that reflects a continued commitment in elevating our sport," said WTA chief Steve Simon.

"This exciting singles and mixed doubles team event will bring together emerging stars and established athletes from both tours to compete on the same stage."

Brisbane, Perth and Sydney will each host two groups of three countries in a round robin format from 29 December to 4 January.

Ties will be comprised of two men's and two women's singles matches and one mixed doubles.

Group winners in each city will play off for one of three semi-final spots in Sydney, with the next best performing team from the groups completing the last four.

"The United Cup marks a major step forward for the game of tennis," said ATP chairman Andrea Gaudenzi.

"Most importantly, it will create incredible new experiences for our fans. We're excited to see the best men's and women's players competing together, with ranking points on the line, to launch the season like never before."