Controversial plans to build a 25-storey block in a conservation area have hit a stumbling block after City Hall said it would be “visually intrusive”.

Residents association, the Jago Action Group said they were “very encouraged” by the report into the 116 unit tower at the Huntingdon Estate in Bethnal Green Road.

The group has sent 700 letters of complaint to Tower Hamlets Council over the plans, which they say do not fit in with the area.

Well known names including Brick Lane-based artist Rachel Whiteread have objected to the building, designed by top architect Amanda Levete for developer Londonewcastle.

Brendon Pinch, Jago’s secretary, said: “They need to change the plans drastically because it looks like it’s supposed to be in Dubai not in Shoreditch.

“It needs to be mindful of the area it’s in.”

While the Greater London Authority’s planning department conceded that the twisted tower was an “innovative, highly sculptural building”, it said it could have a “harmful impact” on the surrounding Redchurch Street conservation area.

The report added: “The site is not, when considered as part of the wider townscape, an appropriate position for a tall building of this scale.”

A heritage impact assessment carried out by Richard Griffiths Architects also concluded that the development would be “alien” to the area.

But Londonewcastle said it found the GLA report to be on the whole positive.

Alongside the tower, a separate development containing 43 affordable homes in between two railway lines Fleet Street Hill is being put forward.

The developer has to provide social housing as part of its planning conditions.

Londonewcastle said it welcomes the findings and said it is “pleased that the building’s architectural, housing and social benefits have been recognised by an independent authority.”

It did not say whether it would be altering the plans to fit in with the GLA’s recommendations.

The council is expected to make a decision on the planning application in the summer.