A council leader has replied to an open letter from an MP which expressed concerns about plans for a new HQ building, with a letter of her own.

Councillor Amanda Hopgood, Liberal Democrat leader of Durham County Council's joint administration, responded to the MP's missive which was posted on social media, and she says the new proposals will save the council more money.

Kevan Jones, Labour MP for North Durham, questioned the proposal to sell a new £50m council HQ at The Sands in Durham city centre to Durham University.

After a review of the previous Labour administration's decision to use the newly-built HQ, council leaders will be asked on Wednesday morning to agree to the sale for the university's business school.

Instead, it is proposed to construct another new "modest-sized civic building" for the council, occupy council-owned offices already under construction at Aykley Heads, and refurbish a Grade II listed building in Stanley.

Read more: MP questions plan to sell The Sands HQ to Durham University

Mr Jones wrote to Cllr Hopgood asking about the costs of the proposals, saying: "I am concerned about the impact that this decision could have on the council's finances.

"I accept this decision is a political one.

"However I do not think that in the interests of value for money for the taxpayers of County Durham, this decision can be taken without some explanation on the financial cost to the council."

Cllr Hopgood wrote in response: "The council will be making a significant financial net gain from the sale of the building, which will be available for use in the future."

Replying to a query about whether a £6m Local Enterprise Partnership (LEP) grant contribution to the Aykley Heads development would need to be repaid to the Government, she said: "We are awaiting clarification of whether or not the grant from the LEP needs to be repaid.

"All figures have been prepared taking into account the eventuality that it has to repaid, although discussions will need to take place with the LEP if the report is agreed tomorrow."

Read more: Durham County Council could end up selling £50m HQ to Durham University

In relation to a question from the MP about the Sands building being constructed on a flood plain, she added: "The university is fully aware of the building’s location in relation to the flood plain, and has undertaken its own due diligence on this matter, including liaising with the Environment Agency.

"As is also made clear in the report, it was already known that the current HQ building has to continue running until the History Centre is ready for occupation, due to the need for relocation of the county records and archives teams.

"This remains the case and the report states that there will be no delay to this timescale caused by not occupying the Sands building. 

"In the proposal going to cabinet tomorrow, the costs for the running of the new office space that are outlined will be less than for the Sands building, and as such are likely to create additional savings for the council, over and above those which were anticipated from occupying the Sands building.

Read more: Labour condemns plans to sell new Durham County Council HQ

"The costs relating to all elements of the project have been accounted for in the proposals.

"This includes everything from the engagement of consultants to support the review that has been undertaken, to the delay in construction due to the issues with the common land that were not resolved by the previous council administration, to the estimated build costs and operating costs of the alternative accommodation strategy being put forward."

She said many financial elements were "exempt from publication" and financial details for building work were in a report which is not publicly available "for commercial sensitivity reasons".

"But I can assure you that they take into account the anticipated market conditions we will be working in," she added.

She said many of the issues raised by the MP would be addressed in the cabinet meeting.