NOTTINGHAM City Council's director of communications is to take five months' unpaid leave – before the authority has completed an investigation into whether public money was used to support a Labour Party publicity campaign.

Stephen Barker's temporary leave began on Friday.

He said he was taking advantage of the offer of unpaid leave extended to council staff as part of the authority's efforts to save money in 2011-12.

But concern has been expressed that Mr Barker will not be available to assist the ongoing inquiry set up by Jane Todd, chief executive of the Labour-controlled council.

The Post revealed last month how council documents suggest that publicity plans for the council and Labour Party were co-ordinated ahead of the 2007 local election. The paperwork, obtained by the Post and Liberal Democrat councillor Tony Sutton, revealed that the council and Labour had planned very similar campaign messages during 2006-2007.

The documents included the printed name "Stephen B". The city council has refused to confirm whether the name relates to Stephen Barker.

It has now also refused to confirm whether Mr Barker was interviewed in the investigation prior to his departure.

Mr Barker is planning to use some of his time off travelling on British waterways in his narrowboat. However, he said he would be back in Nottingham from time to time.

In an e-mail to colleagues, he said: "Please note that I'm going to be 'out of the office' from April 1st to September 1st taking some extended leave which is an option being offered to all council staff as part of a package of voluntary measures agreed as a saving in the 2011-12 budget."

He told the Post: "I won't be disappearing completely because I'll be in work for a week in May, when Nottingham hosts the Local Government Communications Conference, and on a few other days when I really do need to be here. I will see e-mails from time to time."

However, Mr Sutton said: "A period of extended unpaid leave can only be taken with the agreement of senior managers, and it is strange the council should allow it at a critical time in an investigation into such allegations.

" I am concerned this will result in an inability to make significant progress in the investigation, and it will do nothing to restore public confidence ahead of the forthcoming elections."

Andrew Price, leader of the Conservative group on the council, said: "I hope he was spoken to before going on leave, but I am convinced this trip is something he has talked about for a long time."

The documents published by the Post last month also include a printed name, "Harold" and, in handwriting, "Keri".

The council has refused to confirm whether these names relate to Harold Tinworth, a consultant employed in 2006 to give policy and communication support to council leader Jon Collins, and Keri Usherwood, a council communications officer.

The District Auditor previously questioned the legality of the council's posters and banners ahead of the election and said they were "strikingly similar" to Labour Party publicity.

However, the auditor did not find documentation to link the two campaigns and did not refer the matter to court for a judgement on the lawful or unlawful nature of the council's expenditure on publicity.