Dominic Cardy has resigned as New Brunswick's NDP leader, saying he can no longer fight the "destructive forces" within the party.

In a statement released Sunday, Cardy said he "cannot lead a party where a tiny minority of well-connected members refuse to accept the democratic will of the membership."

"Limited time and energy is being wasted on infighting before the election," he said.

Some New Democrats unfortunately believe change and openness have had their time. They want to return to an old NDP of true believers, ideological litmus tests and moral victories. – Dominic Cardy

"That contributed to our loss in 2014 as it will in 2018. Those same destructive forces continue their sterile battle, ignoring the will of the party they claim to champion, using language from the 1930s and policies from the 1970s. There is nothing progressive about this behaviour."

Since 2011, Cardy said, the NDP gained momentum with a "progressive" platform that did not always jibe with the federal NDP mandate, or provincial NDP policies of the past.

"We spoke hard truths," he said in the statement. "Wasteful government spending threatens the poor and social programs we need just as much as reckless tax cuts. Giving handouts to companies while cutting education is not economic development, it's social vandalism. We need a strong government, not a big government."

Best NDP result ever in 2014

In the 2014 election, the NDP failed to win a seat in the legislature, but won 13 per cent of the vote — its best result yet in New Brunswick.

Sunday, however, Cardy said some New Democrats "unfortunately believe change and openness have had their time."

"They want to return to an old NDP of true believers, ideological litmus tests and moral victories," he said.

Party members respond

Party president Sharon Levesque thanked Cardy for his service.

"While many of us are sorry that Dominic will not have more time to build the movement he started, we respect his selfless service to the party and the many unpaid years he put in growing our party," she said.

Kelly Lamrock, acting executive director of provincial NDP and a former Liberal MLA, said he is disappointed Cardy is stepping down.

"I left a far more established party because I thought he was really offering New Brunswick a vision that broke with the past, that made sure we could protect social programs by cutting corporate welfare, by speaking about ending patronage, and that resonated with a lot of people," he said.

News expected on interim leader

"Like a lot of New Democrats today, I'm disappointed," Lamrock added

An announcement is expected this week on an interim leader and setting a date for a leadership convention, Lamrock said.

"The leader has allowed the party to move on to choose someone who can unite the party and that process begins now."