Nastase investigated over Serena 'racial slur'

Nastase, who is Romania's Fed Cup captain, was heard to say to a member of the team at Friday's press conference ahead of a tie with Britain: "Let's see what colour it has. Chocolate with milk?"

"The ITF does not tolerate discriminatory and offensive language and behaviour of any kind," an ITF spokesman told the BBC.

"We are aware of alleged comments made by Romanian captain Ilie Nastase and have begun an immediate investigation so that we have the full facts of the situation before taking further and appropriate action."

The reporting of the remark prompted the 70-year-old former world number one on Saturday to burst into the press centre at Constanta and lambast the Press Association's tennis correspondent for she said two to three minutes.

"Why did you write that? You're stupid, you're stupid," he said to her.

Britain's Press Association said his tirade has also been passed on to the ITF.   

Nastase, who won two Grand Slam titles with the 1972 US Open and 1973 French Open, has previous history with Williams.

In late March he made unsubstantiated allegations about her doping record.

Nastase, who had a reputation as a playboy during and after his playing career, also made a number of inappropriate remarks to Britain captain Anne Keothavong ahead of the weekend tie between the two countries.

He asked for her room number during the official dinner on Thursday and then repeated the request when the captains posed together for photographs following Friday's draw while putting his arm tightly around Keothavong's shoulder.

Williams, one of the greatest players of all time, revealed Wednesday she is expecting her first baby but intends to return to the WTA circuit in 2018.

Williams is due to give birth in September, the same month she turns 36.