Property firm Land Securities has had its controversial plans for a 155m (509ft) skyscraper at 20 Fenchurch Street, London – known as the Walkie-Talkie – approved by Hazel Blears, the secretary of state for communities and local government.

Blears’ predecessor Ruth Kelly called in the plans at the end of last year due to concerns that the Tower of London’s World Heritage status could be under threat, and that views of St Paul’s Cathedral would be obscured.

However, Blears has ruled that the project can go ahead, backing a report by planning inspector Ken Barton that said the benefits of the skyscraper outweigh the negatives.

Mike Hussey, managing director at Land Securities’ London Portfolio, said: “We are delighted that the secretary of state has approved 20 Fenchurch Street. The design by Rafael Viñoly is exceptional.

“We anticipate strong interest from occupiers and we will be preparing the site for development now that we have consent.”

The building will feature a publicly accessible ‘Sky Garden’, which will be the highest public park in London, and will offer visitors an outside roof terrace, botanical gardens, restaurant and a panoramic view of the city.