The ad is being broadcast on television stations in the province and shows people from New Brunswick boarding an airplane for jobs in Western Canada.
"New Brunswickers don't need an ad to tell them that there aren't enough jobs in New Brunswick," Liberal Leader Brian Gallant said Monday.
"This is an ad that is virtually discouraging people to stay and invest in New Brunswick," he said. "It's even demoralizing."
Gallant said the ad is aimed at helping the narrative of the Progressive Conservative election campaign.
But Premier David Alward defended the ad, saying it shows the urgency for supporting the development of natural resources in the province to bring New Brunswickers home from jobs in the west.
"Every day there are families that are living with separation and we believe there are good options long term to see our economy be stronger, our province be stronger, and our people be able to decide to be here and build their communities here," Alward said.
He said many New Brunswickers don't understand the consequences if the province doesn't take advantage of its natural resources such as shale gas.
"It's a message to all New Brunswickers that we need to be saying yes to allow development to take place," said Alward.
The Alward government has been pushing the idea of developing a shale gas industry in the province as a means of creating much needed jobs and revenue. The province is forecast to run a $538 million deficit this year.
There has been strong public opposition to shale gas exploration. A number of protests have included violence and arrests.
Opponents say they have not been properly consulted and believe the practice of hydraulic fracturing to release pockets of gas presents a threat to the environment, particularly water supplies.
Alward refuted Gallant's assertion that the ad is a partisan election commercial.
A spokesman for the premier's office says the ad cost $67,000 to produce and about $70,000 is being spent to broadcast it.
Gallant said that instead of making people believe in the province, the ad is encouraging people to leave.
"It's a bad message and it's a message that taxpayers in New Brunswick certainly shouldn't be paying for," Gallant said.
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