The Council of Trade Unions are defending their ad attack on National's leader.

Their billboards and newspaper ads call Chris Luxon 'out of touch' and 'too much risk'.

National's campaign chair Chris Bishop is accusing Labour of being behind it, but the CTU president says they're not in cahoots with Labour.

President Richard Wagstaff says it's their job to call out someone who's 'going after working people'.

"He's the leader, the buck stops with him. He's put out a set of policies that will undermine working people- it's our job to call him out."

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