Casinos and bookmakers in Great Britain will be forced to pay a £100m-a-year [$125m] levy to fund research, education and treatment of gambling harms, under government plans to be announced as soon as this week.

Labour is understood to be poised to rubber-stamp the previous government’s proposal to do away with a voluntary system that allows industry operators to choose how much to donate to tackle damage caused by gambling and which organisations should receive the money.

The levy, which multiple sources said could be announced by gambling minister Baroness Twycross as soon as Wednesday, is expected to take effect from next April, the Guardian understands.