There's debate over whether parliament is more closely involved in the zero hours contract controversy than previously thought.

Labour claims contractor Spotless is employing staff on zero hours agreements, with Labour leader Andrew Little set to raise the matter with Parliament's Speaker today.

"Now that we know they're here," Little says, "it is right for MPs across the house and now the speaker to action to make sure that we don't have zero hour contracts in parliament."

But Prime Minister John Key says his understanding is that some staff are on flexible, casual contracts, not true zero hours conditions.

"What there isn't a place for, and what the government's concerned about is when someone signs up and says I will work for X, Y, Z hamburger joint and then are stopped actually from working somewhere else even though they might not get hours."