Work has begun on a £22m (US$28.1m, €24.4m) revamp of Edinburgh’s National Galleries of Scotland, which will include a new access path, landscaping and wider steps in East Princes Street Gardens.

The work, once finished, will open up a new area for the gallery’s art collections, as well as transforming former office, storage and display spaces.

The project is being supported financially by the Heritage Lottery Fund and the Scottish government and plans were approved by Edinburgh Council after years of complaints to the museum about accessibility.

"We draw around 2.5 million visitors each year to our Edinburgh-based galleries, and our ambitious plans for the Scottish National Gallery will ensure we continue to meet the needs and expectations of all," said Tricia Allerston, co-director of the Scottish National Gallery.

"With this once-in-a-lifetime project, we will transform the way we show the world’s greatest collection of historic Scottish art, both in the new, light-filled, state-of-the-art display spaces and in the innovative way we will be showcasing the work of Scottish artists alongside our wider international collection."

Sir John Leighton, director-general of the National Galleries, added: "It’s been very exciting over the autumn to see work on this transformational project get started, and as we move out of winter and into spring we’re looking forward to some of our first milestones becoming a reality.

"Unavoidably, there will be some disruption around the site over the coming weeks. We’re grateful for the public’s patience while we create these improvements to the galleries and the surrounding space."

The East Princes Street Gardens entrance to the gallery will now be closed for several months while work takes place. The revamp has been held up by several obstacles and is currently three years behind its original schedule.