The Government is unable to prove councils have enough funding for flood defences, a spending watchdog has discovered.

In a report today the National Audit Office (NAO) said the Department for the Environment, Food and Rural Affairs (Defra) must plug ‘gaps in its understanding’ to assess whether councils have enough resources.

The report found that while many flood schemes are expected to be to be part-funded by councils, a date has not been fixed for a promised review of local government funding for flooding, which is supposed to ‘ensure it is fair and matches the needs and resources of local areas’.

It warned the costs of repairing and maintaining flood defences could increase by between 20% and 70% a year due to climate change and yet the NAO found the proportion of funding going to the 20% most deprived areas of England had ‘reduced substantially’ since 2014.

The NAO said that, although the Government was on course to meet its target of protecting 300,000 homes from flooding by 2021, many of its future plans were ‘not time-limited or measurable’.

It has told Defra to issue a report on flooding funding for councils and whether it is adequate annually, starting in the next financial year.

Head of the NAO, Gareth Davies, said: ‘There is still no comprehensive measure to show that flood risk in England has reduced, even though the current programme is coming to an end.

‘Looking ahead to 2021-27, although the Government has set a clear ambition, the lack of robust measures to track progress mean it will be difficult to demonstrate that its £5.6bn investment provides an adequate response to the changing risk and good value for taxpayers.’

A Defra spokeswoman said the Government invested 'wherever the risk is highest, and where it will benefit the most people and property'.