Public safety concerns, not politics, were behind the axing of the screening of a documentary on the Stop Adani protest movement, a north Queensland council says.

Townsville City Council's talks with police about "emerging community tensions" in the debate around the Carmichael mine project prompted its move to halt the screening at one of its public venues a week out, according to its chief executive Adele Young.

It follows the arrest of a man in Townsville on Monday night for allegedly assaulting anti-Adani protesters, reported threats to activist Ben Pennings, and a controversy that engulfed federal MP George Christensen on Sunday over his apparent online taunt to environmentalists while posing with a gun.

However, the North Queensland Conservation Council (NQCC) insists the council did not mention safety concerns when it first revealed its decision to scrap the booking agreement last Thursday.

Adani's Queensland headquarters in Townsville. ( ABC News )

The environmental group had already paid to hold a local premiere of the Nell Schofield film, A Mighty Force, at Townsville's Old Magistrates Court on February 22, along with simultaneous screenings in other cities.

President of the NQCC, Wendy Tubman, said a council officer told the group in a phone call that her supervisor had instructed her to cancel the booking as council had deemed the film "political".

Ms Tubman told the ABC it was an "outrageous" situation and the NQCC had then written to the mayor, Jenny Hill, to say it had legal advice that the booking agreement was "valid and binding".

On Tuesday Ms Young wrote back, saying council was contractually entitled to cancel a booking for "safety and/or emergency reasons" and would give the NQCC a full refund.

"Following discussions held by council with local representatives of the Queensland Police Service over emerging community tensions surrounding debate on the Adani Carmichael Mine Project, the council is not in a position where it is able to satisfy itself or guarantee the safe and peaceful conduct of the above-mentioned event for our staff or for members of the community," Ms Young wrote.

Ms Tubman said the decision was "certainly not" about safety risks but about an "unacceptable attempt to stifle public education and debate on a matter of huge local, national and international interest".

"At no stage did council ask us what if any security we had planned. At no stage were we contacted by police about any risks associated with this publicly advertised event," she said.

Ms Tubman said the NQCC had found another venue for the screening but was considering legal options.

Council move 'a real worry'

State Greens MP Michael Berkman said that "whichever way you interpret the Townsville City Council's actions here, it seems pretty rotten".

"If they can't be confident that community members are able to safely attend a film screening at the council venue, that's a real worry," he told the ABC.

"What's perhaps more concerning is if council is deliberately stifling community engagement and censoring any backlash around Adani, especially when they've come under fire for their dodgy $18 million funding of Adani's airstrip."

A council spokesman said no councillors, including the mayor, Jenny Hill, were involved in the decision to halt the screening.

Sorry, this video has expired Drone vision of the proposed location for Adani's Carmichael mine

He disputed NQCC's account of being told the screening was cancelled because of "political" considerations, saying the move was prompted by safety concerns.

Ms Hill has been a strong advocate for the Adani project, and declared accepting travel and meal payments from Adani when travelling in a state government-led delegation to India last year.

Earlier this month she insisted Adani must get the project underway within six months to avoid eroding trust.

A police spokesman told the ABC that "council leadership contacted senior police about this matter" on Monday.

"Police are routinely contacted for advice on issues regarding public safety," he said.

"The final decision is a matter for the Townsville City Council."