A drought is expected to be declared in more parts of England on Monday, joining half of the country and the whole of Wales.

The National Drought Group – made up of regulators, government officials, water companies and agricultural bodies - will meet on Monday afternoon to assess the situation across England.

Liz Bentley, chief executive of the Royal Meteorological Society, said the number of people under a hosepipe ban is likely to increase from the 23 million already experiencing restrictions.

She told BBC Radio 4's Today programme the country had experienced an "exceptional, unprecedented summer", which was becoming the "new norm".

Bentley predicted north-west England, which is already classed as being under a less severe "prolonged dry weather" status, would be among those areas where drought could be declared on Monday.

The areas already officially in drought are East Anglia, Hertfordshire, London, Thames Valley, Hampshire, the Isle of Wight, Devon, Cornwall, the West Midlands and Wessex (Dorset, Somerset, Wiltshire, and south Gloucestershire).

There is no single definition of drought, but it usually refers to a period of prolonged unusually dry weather that can have impacts on people, nature and the environment.

Last month, England and Wales saw the driest July since records began in 1836 - while for southern England, it was the driest month ever recorded.

River levels have continued to fall after less than 10mm of rain across England for the seventh consecutive week.

The Environment Agency has warned that low water levels have resulted in potential navigation issues for boats on the Thames, Lark and Ouse.

Reservoir levels have also continued to decline, with almost all across England below normal and five classed as "exceptionally low", according to the agency.

The National Farmers Union (NFU) has warned that continued dry weather could lead to some food shortages.

NFU president Tom Bradshaw said yields of wheat and oats were "very, very poor" this year and warned livestock farmers have had to use their winter feed rations because they have been unable to grow grass.

The week ahead is forecast to remain mostly dry, with temperatures soaring across much of England and Wales.

Temperatures will peak on Thursday before dropping slightly over the weekend - and for England and Wales, there is no significant rainfall expected in the foreseeable future.