Melbourne's busiest court will start sitting on weekends to help reduce the crush in custody and ensure that prisoners can attend hearings, in a move that is expected to cost hundreds of thousands of dollars.


Chief Magistrate Peter Lauritsen has announced that a weekend bail and remand court will be piloted in Melbourne Magistrates Court from Saturday.


The court will hear bail and remand applications for people arrested on Friday evenings and between 10am and 4pm on Saturdays and Sundays.


Mr Lauritsen said this would later be reviewed ''and, if considered appropriate, the pilot may extend to 30 October 2014''.


''The weekend sittings are intended to improve the operations of the Magistrates Court at Melbourne and reduce the pressure of cases listed on Monday mornings at Melbourne and suburban courts. Weekend sittings will also enable accused, being held in custody, to be brought before the court at the earliest time,'' he said.


Fairfax Media has been told that the state government will pay police prosecutors extra to work weekends, but a spokesman for Attorney-General Robert Clark said it was an operational matter for police.


Police Association secretary Greg Davies said that weekend sittings would strain police prosecutors and informants.


Meanwhile, 500 police officers - the equivalent of about 12 24-hour police stations - were taken off the front line every day to look after prisoners in holding cells.


Senior Sergeant Davies said that having about 1200 extra police officers led to more arrests in recent years. ''Those additional numbers provided by the government are being largely eroded by duties they have to perform to prop up the jail system and now the court system.''


He said police were forced to act as prison guards for offenders who were often violent or mentally ill.


''It's hard to apprehend prisoners when you're sitting there babysitting the ones that someone else locked up six months ago,'' he said.


Asked whether weekend sittings would resolve the problem of accommodating prisoners, Mr Clark said it would help ease pressure and was expected to cost ''several hundred thousand dollars, a small price to pay to help ensure greater community safety.''


The Age reported exclusively on October 19 that Mr Clark had been urged to authorise unprecedented weekend sittings to help ease the crisis caused by chronic over-crowding in holding cells in the Custody Centre below the Melbourne Magistrates Court.


He said that prisoner numbers were mainly growing because of tougher parole conditions.