The Treasury was forced to deny earlier this month he considered increasing the levy by up to 39% to plug a black hole of up to £25 billion in the public finances.

In the majority of cases, capital gains tax is not paid on real estate that constitutes a primary residence. But it is paid on investment properties or holiday homes – as well as other assets, such as shares held outside Isas and even paintings and antiques.

Nina Lake, a partner at law firm Howard Kennedy, said uncertainty around the budget could create delays for those currently divorcing because new tax bills could mean settlements would be very different from what is expected.

She said: “For couples divorcing at the moment, we don’t know what the budget changes will bring. The main thing is not to settle your case today, because what is fair today could be really unfair next week.”

Ms Lake also said divorce orders could be changed if capital gains tax rates changed significantly, meaning one half of a couple would receive much less than expected.

Charmaine Hast, a consultant at law firm Collyer Bristow, said: “This could very easily put a strain on a marriage.

“It’s easy to see this being misused to prevent the end of the marriage. It is already sadly common for one partner to use money as a form of coercion in a relationship. And a large tax bill could, in some cases, be another way to do that.”