April UK has announced its plans to withdraw from the UK private medical insurance (PMI) market.
The protection and health insurance provider will close its PMI plans to new business and existing customers will be unaffected until their renewal date, at which point they will be unable to continue the policy.
A spokesperson for the firm said the move follows a decision by its insurance partner to stop bearing risks of its PMI portfolio.
Brian Walters, principal at health insurance brokers Regency Health, said it was very unusual for a provider to withdraw from the market in this way.
He said: "Usually, arrangements are made with another insurer to take over the book. This may still happen, but it's looking less likely with every passing day.
"As things stand, April members will not be offered renewal terms, which will obviously have serious implications for those whose medical circumstances are such that they cannot 'switch' to a new insurer.
"Brokers are unlikely to wait until renewal to move clients who can meet another insurer's transfer criteria, in order to avoid a situation where a client's medical circumstances worsen between now and renewal."
A spokesperson for April UK said support will be provided during the transition, with details of support packages provided directly to those brokers and clients affected.
The company's other business lines will remain unchanged, including income protection, life insurance, personal accident and health cash plans.