The jury in the trial of an architect for the murder of childcare worker Elaine O'Hara has been told the case is not in a position to proceed until Thursday.

Graham Dwyer (42) with an address at Kerrymount Close, Foxrock in Dublin is accused of killing Ms O'Hara at Killakee, Rathfarnham on August 22nd, 2012.

Welcoming the jury into the packed court room this morning, Mr Justice Tony Hunt said the case promises to be long and difficult.

Mr Dwyer denies murdering the childcare worker.

The trial is due to last up to eight weeks - and on day one it has been beset by a slight delay, which means it will not now open until Thursday morning.

The judge has told the jurors that they alone are responsible for judging the evidence, and to avoid as irrelevant any opinions outside court particularly media coverage of the case.

He said in his view even straight forward media reports are partial because of what is left out - while colour and opinion pieces are entirely irrelevant and usually designed to 'flog newspapers'.