Tennis star Maria Sharapova has been banned for two years after committing an anti-doping violation.

The suspension was back-dated to 26 January this year, the day she provided a urine sample after her quarter-final match at the Australian Open.

The ban will expire on January 25th, 2018.

The sample was found to contain meldonium, according to the International Tennis Federation.

Meldonium is a metabolic modulator which is included in the 2016 list of prohibited substances, said the ITF.

In a statement on Facebook, Sharapova described the suspension as "unfairly harsh", and vowed to immediately appeal the tribunal's decision at a court of arbitration.

On March 7th, Sharapova announced that she had tested positive for a banned substance at January's Australian Open.

The 29-year-old sports star was charged and provisionally suspended and soon admitted she had committed the anti-doping rule violation.

She asked for a two-day hearing which took place last month and the ban has now been announced.

In a statement, the International Tennis Federation explained the circumstances behind the decision, saying: "At a two-day hearing on 18-19 May 2016, the Independent Tribunal received evidence and heard legal arguments from both parties, and subsequently issued a reasoned decision on 8 June, which is available below.

"The Independent Tribunal determined that (1) Ms. Sharapova should serve a period of ineligibility of two years; (2) due to her prompt admission of her violation, that period of ineligibility should be back-dated under Article 10.10.3(b) of the Programme to commence from 26 January 2016 (the date of sample collection) and so should end at midnight on 25 January 2018; and (3) her results at the 2016 Australian Open should be disqualified, with resulting forfeiture of the ranking points and prize money that she won at that event."