City planning lawyers are gearing up for a period of uncertainty and delay in the wake of Boris Johnson's election as London Mayor.

Numerous projects across the City are on hold pending reviews to be carried out by Johnson and his new planning team, headed up by Sir Simon Milton – who is an outspoken critic of tall buildings being built in London.

With reviews set to be carried out over the next few months, major tower schemes planned for Blackfriars and Victoria are among those under scrutiny.

Hold-ups will hit planning departments at firms across the City, coming as a further blow to real estate practices which have already faced months of general slowdown in activity.

Herbert Smith planning partner, Matthew White, told Legal Week: "Developers are currently taking stock to see where Boris stands on planning issues and this may impact on activity levels in the short term. There is particular nervousness in relation to tall buildings. We are hoping for a period of continuity from the old regime because projects have such long gestation periods."

Head of planning and public sector at Ashurst, Anthony Curnow, added: "The change of mayor has undoubtedly put developers of large schemes into a period of uncertainty, particularly on tall buildings and on setting off infrastructure cost against affordable housing. We need Boris to come out with a firm policy direction."

Uncertainty has been increased because partners and those in the planning industry are still unclear how Johnson will use new positive planning powers granted shortly before he took on the role. The powers grant the mayor more influence in planning decisions and the power to intervene in boroughs' planning decisions.

Michael Gallimore, head of Lovells' planning practice, said of the new plans: "Everyone is waiting to see how Boris will exercise the new positive planning powers. If he is sensible he will take stock for a few months before intervening on any major projects."

Under Johnson's predecessor, Ken Livingstone, firms were able to reap the benefit of a surge of work on towers built across the City.
Linklaters alone won roles on towers including British Land's new Leadenhall building – dubbed the Cheesegrater – Heron Tower and the Gherkin. Meanwhile, work on the iconic new Shard building has already generated roles for a raft of firms including Eversheds, Freshfields Bruckhaus Deringer and Olswang.