Twelve-time Grand Slam champion Billie Jean King has expressed her sadness after hearing that Elena Baltacha had lost her battle with liver cancer.

The former British number one passed away on Sunday morning at the age of 30 after being diagnosed with the disease in January this year.

King wrote on Twitter: "Saddened to hear about Elena Baltacha's passing. My fondest memory w/Bally was sharing a wonderful chat when we met the Queen at @Wimbledon."

Baltacha, who won 11 singles titles during her career, retired from professional tennis back in November last year.