The long-awaited reopening of Norwich Castle's keep after a major multi-million pound revamp has been delayed - by a year.

And museum bosses have had to get an extra £1.4m from lottery chiefs to help cover rising construction costs for the facelift for the city's landmark 900-year-old keep.

Eastern Daily Press: Work inside Norwich Castle's KeepWork inside Norwich Castle's Keep (Image: Archant 2021)

When work on the £13.5m National Heritage Lottery funded Royal Palace Reborn project got under way in 2020, the ambition was for the new-look museum to open next spring.

But Norfolk Museums Service chiefs have confirmed the keep revamp is unlikely to be completed until September next year - with the full re-opening of the revamped museum pushed back to Easter 2024.

Eastern Daily Press: Dr Robin Hanley, assistant head of Norfolk Museums ServiceDr Robin Hanley, assistant head of Norfolk Museums Service (Image: Archant)

And Dr Robin Hanley, assistant head of museums, said extra money - £1.37m - had been obtained from the National Heritage Lottery Fund to help cover increased construction costs.

A major element of the work on the keep is to install about 200 tonnes of steel to provide walkways and floors.

Eastern Daily Press: A visualisation of a new bridge that will provide direct level access to the principal floor of the Castle Keep, revealing currently hidden views of the Bigod Tower and east façade of the Keep.A visualisation of a new bridge that will provide direct level access to the principal floor of the Castle Keep, revealing currently hidden views of the Bigod Tower and east façade of the Keep. (Image: Feilden + Mawson)

The availability of steel and other construction materials has been hit by supply chain issues, which worsened further after Russia invaded Ukraine.

The impacts of Covid and discoveries during work has contributed to the delay.

While other elements of the revamp, such as the new cafe and shops, are due to be completed by Easter next year, the keep itself - and a new medieval gallery of objects on long loan from the British Museum - is further off completion.

Eastern Daily Press: A visualisation of the ground floor of the Keep.A visualisation of the ground floor of the Keep. (Image: Haley Sharpe Design)

Dr Hanley told a committee of councillors: "We are looking at the main entrance, shops and cafe areas back with us for Easter next year and we're expecting construction works to be completed in September next year on the main keep itself.

"Realistically, [we are looking at] soft openings at the beginning of 2024 and all bells and whistles for Easter 2024."

Eastern Daily Press: Work on Norwich CastleWork on Norwich Castle (Image: Archant)

He added: "We are affected, as other construction projects are, by the very volatile conditions within the construction industry and that includes supply chains and elements like steel, along with other materials."

The ambitious project, which museum bosses hope will attract 100,000 more visitors to the castle each year, is recreating the keep's original 12th Century layout.

Eastern Daily Press: A visualisation of how the recreated Great Hall in Norwich Castle's keep would look.A visualisation of how the recreated Great Hall in Norwich Castle's keep would look. (Image: Haley Shape Design)

Parts of the museum, including the keep, have been off-limits to the public during the work.

Eastern Daily Press: Delays mean Norwich Castle's Keep will not reopen until 2024Delays mean Norwich Castle's Keep will not reopen until 2024 (Image: Archant)