A woman tries to avoid being taken away by police at protests outside Westpac Stadium in October 2017.

The cost of escalating tensions between police and protesters in Wellington is ballooning.

The latest showdown where about 200 demonstrators tried to block delegates at the Petroleum Exploration and Production Association of New Zealand oil summit at TSB Arena in March, required 160 officers at a cost of $186,000.

Figures released under the Official Information Act also show protests involving about 300 activists from Auckland and Wellington and police at the annual defence industry forum at Westpac Stadium in October took 101 officers and cost $112,000.

KEVIN STENT/STUFF Operation commander Inspector Brett Amas said the cost of individual police operations would always vary depending on the requirements of each event. (File photo)

In 2015 when the New Zealand Defence Industry Association Forum – called a "weapons expo" by activists – was held at TSB Arena the bill for policing about 150 protesters was $20,000 with 58 officers on hand.

READ MORE:

* 'Lack of neutrality' present in policing of defence industry expo protest, lawyer says

* Police arrest anti-weapons protesters trying to block off Westpac Stadium

* Peace protester feels vindicated after police trespass charge thrown out

* Protesters blockade petrol and gas exploration conference in Wellington

* What is the New Zealand Defence Industry Association forum?

District operations manager Inspector Brett Amas said the cost of individual police operations would always vary depending on the operational requirements of each event.

KEVIN STENT/STUFF Protesters at Westpac Stadium in October, 2017. Policing the protest required 101 police and cost $112,000.

"Police deploy appropriate resourcing to every situation that is presented to us, and no two operations are the same." Police fully respected the lawful right to protest, as well as ensuring that right was upheld alongside the rights of people to go about their lawful business and to ensure public safety, Amas said. Laura Drew, from Peace Action, said it was troubling that police resources were being used to actively stifle political dissent. "It’s also inappropriate that the police are becoming more violent and aggressive towards protesters while acting as taxpayer-funded security service for big businesses." Drew said protesters had been painted as troublemakers for hundreds of years, and "categorically targeted by police, spies and the justice system". Associate Professor Kerry Taylor, who has researched the history of the left and protest in New Zealand, said protest was part of a long-standing tradition of civil disobedience that went back at least to World War I. It was often characterised by mutual distrust between police and protesters who both viewed their actions as legitimate.