One of the new billboards on SH2 says: "This road isn't very safe."
The next reads: "National was building a 4-lane highway here."
And the third says: "But Labour cancelled it."
Muller told the Bay of Plenty Times that the National Government committed to starting the Tauranga Northern Link while it was in office.
He said National had already budgeted for the first 7km of the road, a tender process had begun and construction was due to start in October.
"And these guys stopped it," Muller said, referring to the Labour Government.
However, Warren-Clark disputed that and the signs' messaging.
She said it was important to differentiate between National's election promise of a four-lane highway from Bethlehem to Katikati, and the Te Puna section of the Tauranga Northern Link.
Warren-Clark said the four-lane highway election promise was "never funded, never costed and never contracted".
Work on the Te Puna roading project, however, had commenced and Labour is "absolutely going ahead with that", she said.
"What we are not going ahead with is the four-lane highway, which is a separate thing altogether."
Warren-Clark acknowledged that the four-lane highway was something the community had been asking for, for a long time.
She said that section of SH2 had been neglected "for many, many years" including under the National Government.
Warren-Clark said her Government was funding safety improvements across the country, including in the Bay of Plenty, and was allocating the money fairly by population base.
"I implore people to drive safely and carefully, so they get home safe to their families this Christmas season."
Meanwhile, Muller said he wanted to keep the SH2 issue, which has generated plenty of debate and protest in 2018, "front of mind" as the new year began.
"I want to make this a thorn in the Government's side, to the point that it gets so irritating they fix it."
Muller said it was not political rhetoric.
He said everybody in the community knows the road needs to be built.
"It's not an unreasonable request."
Muller acknowledged the work done this year by the Fix the Bloody Road campaign and said he wanted to add his voice to the ongoing concerns expressed by the group and its supporters.
Fix the Bloody Road campaigner Andrew Hollis said it was good to have the Opposition keeping the campaign going, and the pressure on, over summer.
"It's also an extraordinary high crash area and if anything else ... I'm hoping it gets people to maybe slow down or be aware that it's a risky area," he said.
"I think the billboards will help with that and maybe keep our community safe for a few months over the busy time, and probably let the ministry and the NZTA know that we're not going to sleep."
