Labour appeared to be in disarray on Wednesday over ambitions to clean up the River Thames for swimming.

The mayor of London, Sadiq Khan, announced ambitions to prioritise an area of the river in Teddington, south-west London, to make it safe and clean for swimming as part of a new 10-year strategy to reduce pollution in the river and encourage people to spend time in and around it.

Supporting Khan as he made the announcement was the environment secretary, Steve Reed. But Reed just last week approved the next stage in the development of a controversial scheme to allow Thames Water to pump 75m litres a day of treated sewage into the river at the same spot in Teddington.