Opened in 1901, the Grade II*-listed Arts and Crafts building by Harrison Townsend was redesigned four years ago by Allies & Morrison - a £13.5 million extension project which included a new café and entrance.
Now the museum, which also houses the country's largest collection of musical instruments, wants to revamp 400m 2of exhibition space as part of a new £1.2 million refurbishment scheme.
The original building was described by Pevsner as 'one of he boldest public buildings of its date in Britain' with a 'strong dominatingly curved' facade similar to that of Whitechapel Gallery - Townsend's other gem.
Describing the planned work, a spokesman said: 'The look and feel of the design must respond to the architectural space. It is anticipated that mechanical, electrical and lighting schemes will require significant re-design.'
The winning designer, who will be selected through the OJEU process, will be asked to take the proposals through to RIBA stage C/D so that a full Heritage Lottery Fund application can be made.
For more details about the project, visit www.ted.europa.eu(contract notice 2006/s 147-158896).
The deadline is 15 September.