Labour peer Lord Winston's attack on Government funding of the NHS, and Tory support for his stance, has sparked a furious debate on the future of medical insurance.
The internationally-recognised fertility expert, who is best known for the BBC documentary series The Human Body, said patients face a stark choice between higher taxes or some form of compulsory health insurance similar to France or Germany.
David Ashdown, spokesman for health insurer Western Provident Association, thinks it is only a matter of time before more widespread charging is introduced in the NHS.
He said: "It's a way off yet, but we could see more people making a contribution at the point at which they use the NHS."
He added that WPA has seen a steady increase in self-paying patients for surgery such as varicose veins and cataract removal and also in demand for its high-excess, low-premium health insurance policy.
But BUPA is concerned the current funding debate has become polarised and does not believe private insurance alone can solve the problem.
It said: "We feel the private sector can be complementary to the NHS and there should be a debate about how the two sectors combined could provide a better option to patients."