NHS patients in England are being urged to plan ahead for appointments as rail strikes are set to cause travel chaos next week.

Speaking ahead of the strikes, the NHS’s top doctor reminded people that “the NHS remains open” as he called on people to seek care when needed.

Millions of people are seen and treated in the NHS every week.

The strikes could have a particular impact on hospitals in London, many of which have limited parking capacity for those considering driving to appointments as an alternative.

As well as affecting patient appointments, the strikes may also hamper NHS staff commutes.

Half of Britain’s rail lines will be closed during strikes on June 21, 23 and 25 by the Rail, Maritime and Transport (RMT) union.

Transport for London has also “strongly encouraged” people not to travel on London Underground on June 21 because of a 24-hour walkout by the RMT and Unite.

Professor Sir Stephen Powis, national medical director for the NHS in England, said: “With rail strikes expected across the country next week, I am urging those who have appointments booked in to plan ahead and look at alternative options for getting to their GP practice or hospital if needed.

“The NHS sees millions of people every week for urgent and routine care and it is vital that people access the care they need despite disruptions – the NHS remains open, so please do continue to come forward.”