Former tennis world No. 1 Serena Williams is scheduled to play in Washington in July for the Washington Kastles of World TeamTennis, announced the nine-team US league, which will stage a 36th season from July 4-24.

Williams is still recovering from the removal of a blood clot in her lung as well as a nagging foot injury.

The reigning Wimbledon champion had said she was hopeful of a summer return, but was unsure exactly when she might be back on the court.

The 13-time Grand Slam champion has not played a top-level match since last year's Wimbledon final after cutting her right foot on broken glass at a restaurant last July.

She also suffered a pulmonary embolism and underwent an emergency operation at Cedars-Sinai Medical Center in Los Angeles last week, a health scare she called "the scariest moment in my life".

"Luckily enough, I was able to catch it soon enough that my career won't be affected," Williams said. "I love tennis and now more than anything I have so much to look forward to just playing. I really just want to come back and do well."