Oscar Pistorius arrives at the North Gauteng High Court for the opening day of his murder trial, accused of murdering his girlfriend. Photo: AFP

Pretoria - Oscar Pistorius arrived at the High Court in Pretoria on Monday for the start of his murder trial.

Pistorius, 27, arrived at court dressed in a suit and tie, his face pasted with a nervous expression as media and the mother of 29-year-old girlfriend Reeva Steenkamp looked on.

June Steenkamp looked at Pistorius without emotion as he entered courtroom GD.

He avoided looking at the public gallery, where she was sitting.

Pistorius was ushered into the court through a side entrance and took a cushion as he sat down in the dock. He took a sip of water and shrugged his shoulders.

He was seen talking to his defence team, and whispering into his advocate Barry Roux's ear.

Earlier the prosecution and the defence team left the court room through the judge's entrance, apparently to hold a meeting prior to proceedings.

Pistorius is accused of shooting dead his girlfriend, Reeva Steenkamp, at his Pretoria home on February 14, 2013. He has claimed he had mistaken her for an intruder.

Pistorius siblings Aimee and Carl sat in the same row as the Steenkamp family.

The Pistorius and Steenkamp families left a large gap between themselves on the bench.

Carl seemed uncomfortable as looked around the courtroom and whispered to his sister.

The Pistorius siblings have in the past court appearances shown a united front. During Pistorius's bail application over a year ago, they were seen praying together in the court before the proceedings began.

Steenkamp's mother, June, and those who accompanied her were dressed in black. She sat quietly in the gallery, waiting for the proceedings to begin.

Journalists were asked not to speak to the judge or the prosecution teams.

Lulama Luti, spokeswoman for the Office of the Chief Justice, told media not to speak to them and ordered reporters not to take pictures of the courtroom with cellphones or tablets.

National Prosecuting Authority spokesman Nathi Ncube, addressing media in the public gallery, said they would not discuss the merits of the case.

The proceedings in the wood-panelled courtroom will be broadcast live on television and radio, with the initial indictment listing 107 witnesses to testify for the State.

The trial was due to begin at 10am. - Sapa, Reuters, AFP