Former News of the World editor Andy Coulson has gone on trial in Scotland accused of committing perjury.

He is accused of lying under oath during the 2010 perjury trial of former MSP Tommy Sheridan.

Coulson, 47, former director of communications for David Cameron, denies the allegation against him.

The trial, at the High Court in Edinburgh, is expected to last four weeks.

Prosecutors allege that Coulson, from Kent, made false claims on December 9 and 10 that year while he was a witness at the trial at the High Court in Glasgow almost four-and-a-half years ago.

The indictment alleges that Coulson falsely stated that before the arrest of private investigator Glenn Mulcaire and News of the World journalist Clive Goodman on August 8 2006, he did not know that Goodman was involved in phone hacking, and did so together with Mulcaire.

It claims he falsely said he did not know that payments were made to Mulcaire by Goodman and that he did not know of Mulcaire's "illegal activities".

It also alleges that Coulson said he did not have any email exchanges with Goodman in relation to Mulcaire.

The Crown further alleges that Coulson falsely stated that he did not know of Mulcaire, had not heard his name, did not know that he was employed by the News of the World newspaper, and did not know that Nine Consultancy was Mulcaire.

It is claimed Coulson falsely said he had no knowledge of payments being made to corrupt police officers by staff of the News of the World while he was employed as an editor there.

Prosecutors allege that between October 10 2005 and August 8 2006, Coulson had heard of Mulcaire who, as well as being a private investigator, was contracted to the News of the World.

They allege he knew that Goodman was involved in phone hacking and knew that he did so together with Mulcaire.

The three-page indictment claims that Coulson knew that Goodman made payments to Mulcaire of £500 a week until February 2006, followed by payments amounting to £4,800.

The prosecution also alleges that Coulson knew that Mulcaire was employed by the News of the World and had email exchanges about him with Goodman, in which Mulcaire was referred to as "Matey".

It is claimed Coulson knew that Nine Consultancy was the business name under which Mulcaire operated and that he knew of Mulcaire's "illegal activities" insofar as they related to phone hacking.

It is also alleged that between December 1 2002 and January 26 2007, while editor and deputy editor of the newspaper, Coulson understood that payments had been made to corrupt police officers by Goodman.

The payments included £750 in or around December 2002, £1,000 around January 2003, and £1,000 around June 2005.

These were made to procure a "green book" or other similar directories containing information including telephone numbers relating to the Royal Family and their staff, the indictment states.

The trial is being held before judge Lord Burns.The judge told the jury of nine men and six women Coulson was the former director of communications for the Prime Minister.

He said there has been a "great deal of information" about Coulson, Mr Sheridan and the subject matter of the charge in a variety of media and on the internet.

But he reminded the jury they had taken an oath to try the accused "solely and exclusively" upon the evidence they will hear from the witness box.

That means they must "ignore" and put out of their minds any information from any other sources, he said, including from the television, newspapers, magazines and the internet.

"You also have to put aside any view you may have formed about any issues raised in this charge," Lord Burns said.

The judge said they may have formed views about Mr Sheridan or the accused "and their activities, political or otherwise".

But he added: "It would be quite wrong for you, as a jury, to be influenced in any way by such views or opinions."

The court was later read a document of evidence which has been agreed by the Crown and the defence in this case, known as a joint minute.

It stated that, following publication of a series of articles about him in the News of the World, Mr Sheridan raised a defamation action in Scotland's Court of Session against the newspaper's publishers News Group International Ltd.

The jury in the 2006 defamation action ultimately decided that the socialist politician had been defamed by the newspaper and the tabloid was ordered to pay him £200,000 in damages.

In the document, read to the court by Crown representative Gillian Ross, the court also heard that Mr Sheridan's perjury trial at the High Court in Glasgow towards the end of 2010 was in respect of evidence he gave in the earlier defamation action.

During the trial, Mr Sheridan dismissed his lawyers and conducted his own defence. Coulson was later called as a defence witness by Mr Sheridan over two days.

It was alleged in the High Court trial that Mr Sheridan falsely stated that he had not attended Cupid's health club in Manchester with others towards the end of 2001 or had ever visited a swingers club.

The court was also read a "statement of uncontroversial evidence" lodged by Coulson in the current trial.

It claims that, on the second day of his speech to the jury on December 22 2010, Mr Sheridan said in respect of the relevance of Coulson's evidence: "The reason I risked my defence to cite the likes of Glenn Mulcaire and Andy Coulson to give evidence wasn't because I thought they were going to help my defence, it was because I think I have a public service and a public duty to try to expose wrongdoing."

Mr Sheridan is said to have stated that there were "other issues that have to be considered about conduct in public life, about power, about who can do things and who can break the law and get away with it".

Coulson denies the charge against him.

The trial, before Lord Burns, will continue on Tuesday.