Russian Tennis Federation president Shamil Tarpischev has been forced to publicly apologise for his slur against the Williams sisters, Serena and Venus.

The International Tennis Federation came under fire from Martina Navratilova on Monday for failing to act after Tarpischev described the Williams' as "brothers".

The Womens' Tennis Association responded swiftly to Tarpischev's remarks by banning him for a year and issuing a fine of 25,000 US dollars (Dhs 91,827).

Navratilova, who won a legends exhibition alongside Marion Bartoli at the WTA Finals in Singapore yesterday, said she was baffled by the ITF’s lack of reaction to the situation. 

“I think the WTA has taken the proper steps in this instance and pretty swift steps. The silence from the ITF has, to me, been pretty deafening,” said the 18-time Grand Slam champion.

“I think they’re the ones that actually have more of a possibility of doing something because Shamil Tarpischev is the head of the Russian Tennis Federation, which falls under the ITF and is also the Fed Cup team captain, which again falls under the ITF.

“So the WTA has done all they can do. They have certainly shown that they have Serena’s back, and Venus’ back, as they should.

“He might have thought that the comment was funny but it was anything. The WTA has done what they can and you just take it one instance at a time.

“But certainly that kind of bullying, that kind of comment can’t be tolerated from anybody but particularly not from a high up official in the tennis world.”

Ricci Bitti believes Tarpischev's apology and the WTA's actions are a sufficient punishment.

Speaking to Press Association Sport, Ricci Bitti said: "The ITF was very disappointed when it learned that Shamil Tarpischev, long-time President of the Russian Tennis Federation, made derogatory remarks about the gender of Serena and Venus Williams.

"Mr Tarpischev has taken an important step by sending his apology to the ITF, the WTA and to the Williams sisters.

"Although Mr. Tarpischev assured us his comment was meant as a joke, we made it clear to him what he said is inappropriate in any context.

"We hope his acceptance of fault in this matter, which includes the penalty assessed by the WTA Tour, will allow all of us to move forward."