The National Party says it will campaign on tougher measures for benefit fraud in the November election.
But opposition parties say it will end up attacking some of the country's most vulnerable people.
The Government says since September last year, it has removed more than 7400 people from the unemployment benefit who are no longer eligible.
Social Development Minister Paula Bennett says some of those were for relationship fraud, which she says is difficult to prove.
Ms Bennett says National will campaign on a raft of welfare changes with a special focus on benefit fraud.
But Green Party MP Catherine Delahunty says National's move could see those most vulnerable put off from applying for help they are entitled to.
Though the Labour Party supports a crackdown on benefit fraud, deputy leader Annette King says National is off the mark in terms of its plans for the future and creating employment.