A temporary service will be offered via a mobile library

It will remain shut for at least two weeks while scaffolding is erected and further assessments carried out.

The decision was taken on Tuesday and Swansea Council said alternative services were being put in place.

Last year the authority revealed plans to relocate the library from its current home on Alexandra Road to County Hall on the seafront.

Cabinet member for culture, Gerald Clement, said on Wednesday the council had been monitoring the state of the building.

"It's become clear over the past week that a third-floor wall of the building needs support to be carried out," he said.

"Initial scaffolding work will be carried out over the next two weeks along with an assessment of any further activity required."

The problem is being blamed on a rotting beam in the central part of the building, shared with Swansea Institute.

Internet service

Contractors will be on site on Monday to begin replacing it with a steel girder.

The work will involve removing a substantial part of the building and every brick will need to be numbered, documented and placed back to its original position because it is a listed building.

Over a million people visited Swansea's libraries last year.

The Central Library is home to the city's main reference library.

The council said it was taking a number of steps to minimise disruption to library users.

Head of library services Peter Gaw said: "Members of staff are being stationed outside the library over the next couple of days to advise customers.

"Library customers can use Swansea's other libraries and they can also tap into our services on the internet.

"There is a temporary book drop-in service at the Gyn Vivian Art Gallery situated opposite the library where customers can return their library items and we are planning to offer a temporary lending service via a mobile library."