"An increase in gang membership means an increase in crime in our communities and more victims."
The figures, provided to Nash by the police, break down the number of people on the National gang list by regions.
The numbers show a 30 per cent increase in the number of gang members in the Bay of Plenty (1058 in October 2017 compared with 1380 in August 2019).
There has been a 44 per cent (386 to 556) increase in Waikato over the same period.
When asked for a response on the increase in gang numbers, a spokeswoman for Nash said that, over that same period, 1200 offenders from Australia had been sent to New Zealand.
She also pointed out that, as part of the Government's commitment to tackle gangs, 500 of the promised 1800 new police officers by 2020 will be specifically assigned to preventing organised crime.
Earlier this week, the Herald revealed National was looking into a policy which would require gang members to prove they don't have illegal income before they receive the benefit.
"I can confirm we are currently working on a gang plan for next year which will crack down on them and the misery they peddle," he said on Twitter.
To combat the Government's so-called soft on crime approach, Bridges has today confirmed the party will release a comprehensive gang plan next year which he said would "crack down hard on gangs".
Details are limited at this stage, but the document is likely to contain a raft of potential policies the party will bring into the 2020 election.
"Gangs do nothing but peddle misery and create more victims," the National leader said.
"National is the party of law and order and will ensure that there are fewer victims of crime."
Earlier this week, Waikato Mongrel Mob Kingdom president Sonny Fatupaito issued a press release saying the branch was starting a women's chapter.
Bridges said this is just one example of how "emboldened the gangs have become".