Planning permission will cap London’s efforts to provide new homes at just two-thirds of official targets if approvals continue at the current rate, according to new research from London estate agents Stirling Ackroyd.

London’s planning system is allowing new homes at an annualised rate of just 27,470 as of Q4 2014 – or just over two thirds (69%) the political target for 40,000 finished new homes each year – an objective announced by George Osborne and Boris Johnson in February and underlined in March’s Budget, ahead of May’s General Election.

Analysis of planning applications across all of the capital’s 32 boroughs plus the City of London shows just 6,780 homes were given planning permission last quarter, spread across 826 different sites. These approvals represent 80% of all potential homes receiving a planning decision in Q4 2014. This is out of plans for 8,632 possible homes in Q4. By contrast, if 100% had been approved, this could have allowed an annualised rate of up to 34,530 new homes, or 86% of the official target rate.

In reality the number of homes reaching completion stage currently stands at an annualised rate of just 18,440 – after Q4 saw just 4,610 properties finished in the space of three months.