Councillors have agreed to lend the owners of the Theatre Royal £1 million to plug a funding gap in on a over-budget revamp.

Scottish Opera's request for financial help was unanimously agreed at a meeting of Glasgow City Council's executive committee today.

It is understood the Scottish Government has also agreed to offer a £3 million loan.

The Theatre Royal underwent a £14.5 million redevelopment and reopened in December last year.

The council gave an initial grant of £850,000 and the project was also funded by awards from Scottish Government, Creative Scotland, Heritage Lottery Fund.

The extensive work has seen the 1500-capacity Victorian auditorium linked to the four-storey “lantern” complex.

The 19th century theatre was due to open last May but this was twice delayed as the project ran over time and over-budget because of unforeseen difficulties - including adverse weather conditions.

A report on the theatre, which was tabled at the Executive Committee today, states: "The project has been complex due to the intricate design, the required physical connection of listed and new buildings, site constraints and extraordinary ground conditions.

"All of which have led to significant cost increases and which could not have reasonably been foreseen."

It adds: "To support these financial pressures the Scottish Government has indicated that it will provide a loan of up to £3 million.

"The Scottish Opera has requested a further contribution of £1 million from the council to bridge the gap between all other sources of income."

Councillors also agreed to give £1 million to help fund the development of The Briggait Centre and the creation of Scotland's first £4 million dance, theatre and street arts arena.

They will also give £861,000 to the Glasgow Film Theatre - half of which will be repaid as a loan - to support phase two of a revamp.

Committee chairman Archie Graham invited councillors to approve the financial rewards and this was agreed without debate.

The A-listed Theatre Royal was built in 1867.

It was purchased with public support by Scottish Opera, from STV, in 1974.

In 2005 Scottish Opera leased the theatre management to Ambassador Theatre Group but the theatre remains the performance home for both Scottish Opera a Scottish Ballet.