It's blaming the 'long-term forecast of dry weather' but hasn't confirmed when restrictions will come in.
The UK's biggest water company has announced it intends to introduce a hosepipe ban in the coming weeks.
A spokesperson for Thames Water - which supplies Oxfordshire - said given the heat and dry weather it wants to impose a temporary use ban.
It has written to the Environment Agency, but can't yet confirm when the ban will start due to 'operational and legal procedural requirements.'
A spokesperson for the water company said: “Given the long-term forecast of dry weather and another forecast of very hot temperatures coming this week, we are planning to announce a temporary use ban in the coming weeks.
“We have written to the Environment Agency to update them on our approach and informed Ofwat.
“The timing is not confirmed due to a number of operational and legal procedural requirements but we will be updating our customers, partners, regulators and stakeholders at the earliest time to ensure a co-ordinated approach.
“In the meantime, we continue to urge our customers to only use what they need for their essential use.”
Thames Water's restrictions will affect around 15 million people across England.
Southern Water and South East Water have already imposed hosepipe bans on some of their customers.
Meanwhile, a four-day amber heat warning's been announced for England and Wales from Thursday.
The Met Office says temperatures could reach the mid-30s, with potential travel disruption and the "likely" chance of illnesses like sunburn and exhaustion.