The handover of a multi-million pound office block in Glasgow to Scottish Power has been delayed by almost a year.

The 14-storey structure on the corner of St Vincent Street and Elmbank Street was scheduled to be completed “by late 2015,” according to architects.

The land - which was once the base of the former Strathclyde Regional Council - lay vacant for many years after a planned £120m skyscraper project was scrapped in 2008 during the financial crisis.

In 2012 Scottish Power announced that it had secured a 25-year lease on a new office complex that would become a flagship headquarters for 1,500 staff.

But three years after Glasgow City Council gave the green light to the £100m project not one of the power company’s employees has moved in.

And a source close to the project warned that it could be several months before the building is ready to be occupied.

“There have been delays,” said the source, who asked not to be named. “We are hoping to hand over at least six floors in September.”

Architects Page/Park were tight lipped yesterday about the cause of the delay.

David Shaw, of the Glasgow-based firm, said: “There are lots of lots of contractual reasons why I can’t speak to you about this.”

An official announcement on Page/Park’s website in May 2013 welcomed the council’s decision to rubber stamp the project.

“Construction work will commence later this year, with the development expected to be complete by late 2015,” it stated.

In December 2014 Page/Park posted a festive rhyme about a site visit which appears to be a homage to 19th century poem ‘A Visit from St. Nicholas’.

It begins “Twas the week before Christmas” and ends with the lines, “Time to embrace the pre-Christmas cheer; foundations are laid for the forthcoming year.”

There are no further progress updates on the Page/Park website, however Scottish Power said weather had been an issue.

A spokesman for Scottish Power said: “The construction programme was affected by the severe winter weather, like other construction projects in Scotland have been. As well as multiple storms, we experienced the wettest winter on record.

“Good progress has been made in the last few months, with the majority of external work now complete and work well underway on the interior fittings. The building will be handed over to us later this year.”

Announcing the new headquarters in July 2012, Ignacio Galan, chairman of Iberdrola and Scottish Power, said: “Our plans in the UK in the coming years require an office complex that is fit for purpose to deliver and manage these investments.

“Following the integration between Iberdrola and Scottish Power in 2007, we have invested £4bn in the UK and made a commitment that Glasgow would remain as the central location for our company in the UK.

“This new development will ensure Glasgow remains home to Scottish Power's UK headquarters for the long term and will be a hub for delivering the £10bn of planned investment over the coming years.”

The firm's chief corporate officer, Keith Anderson, added: “Our new office will be modern and functional, and will bring together many Scottish Power people from across the business to be located in a single central site.”