The resources minister Matt Canavan has defended an extraordinary spray against engineering firm Aurecon over its decision to sever ties with Indian energy company Adani.

Canavan had labelled Aurecon’s decision “weak as piss”, and on Thursday rejected claims from the Greens that he is a hypocrite for using public pressure to bully the company while criticising anti-coal activists.

Aurecon has decided to end its commercial relationship with Adani, including work on the Abbot Point Coal terminal in north Queensland and a solar project in Whyalla in South Australia, due to a campaign targeting Adani and its contractors in a bid to prevent the Carmichael coalmine.

Canavan responded by describing Aurecon as “a bunch of bedwetters”, telling Radio National on Thursday he did so because he was “sick and tired” of the company’s “PR rot”, noting that it had not cut ties with other coal ports.

“I would’ve had a lot more respect for Aurecon if they’d come out and been upfront saying they can’t do this because they’re under pressure … but to come out and try to wrap it up as a sustainable decision, give me a break.”

Canavan said he “made no apologies” for his language, explaining Aurecon’s behaviour “giving in to bullies … has to be called out” and claiming it was “time to be upfront”.

The Greens leader, Richard Di Natale, has labelled Canavan a “hypocrite because he criticises campaigns against companies that don’t support his interests and yet here he is targeting individual companies [which] for their own reasons have made financial decisions because they understand coal has no long-term future”.

Canavan responded that he has “no problem with people criticising the coal industry” but he objects to “people breaking the law” and “holding Brisbane to ransom” by holding up CBD traffic.

On Tuesday the Palaszczuk Labor government proposed new laws with stronger penalties and expanded police powers, including to make it illegal to possess a device used for locking on, in an attempt to crack down on an escalating campaign of civil disobedience.

Canavan accused environmental protesters of “wantonly [breaking] the law” and said the Queensland Labor government had “finally” decided to crack down on it after months.

Aurecon had not been directly involved in the Carmichael mine – it had been the engineering, procurement and construction contractor at the Abbot Point coal terminal since 2005. Adani bought the terminal in 2011.

On Wednesday Adani responded by saying it was “surprised” by Aurecon’s decision but is already in discussions with other businesses that had expressed an interest in taking up the work.

“There has been a concerted campaign by extremists against our Carmichael project and businesses that partner with us,” it said. “It has not succeeded and construction of the Carmichael project is well and truly under way.

“We have repeatedly demonstrated that we will not be intimidated or deterred from delivering on our promises to Queenslanders, Australians and the people in developing nations who desperately need affordable energy to help lift them out of poverty.”