NSW Labor is demanding to know how much taxpayer funding has been promised to three sporting clubs based at Moore Park to compensate them while a new stadium is built.

The Berejiklian government announced last week that it would spend about $2 billion to replace Allianz Stadium at Moore Park and ANZ Stadium at Sydney Olympic Park.

Eighteen months ago, the three clubs - the Roosters (rugby league), Sydney FC (A-League soccer) and NSW Waratahs (rugby union) - warned loudly that being without a home stadium for years would have a disastrous impact on their business.

But the three clubs last week all welcomed the decision to build a new stadium at Moore Park, even though this would dislocate them for two or more years.