"OMV New Zealand diverted considerable resources to dealing with the illegal protest such as support vessels and medics to ensure the safety of the protesters."
Selischi said he expected regulators to take action against the pair, while BusinessNZ called for anyone who supported the pair to be prosecuted.
Kirk Hope, chief executive of BusinessNZ said any non government organisation that helped enable the protest should face prosecution under health and safety law, as both the protesters and those who went to assist them were put in danger.
"If this was a small company that was putting their employees in this situation there's no question about them being prosecuted," Hope said.
"They're clearly putting themselves and other people in danger."
Previously Hanafin and Fitzjohn have been involved in high-profile protests against OMV led by with Greenpeace, which has extensively targeted the Austrian oil and gas company.
When Hanafin spent 14 hours scaling Wellington's tallest building, the Majestic Centre - which is home to OMV's Australasian offices - he was described as a "Greenpeace climber" by the international organisation.
In 2016, Fitzjohn was one of a group of Greenpeace activists who were convicted and discharged after they chained themselves to a research vessel they claimed was being used for oil exploration.
On Tuesday, Greenpeace denied any involvement in the pair's protest, saying it was not part of the "coalition" which helped them.
"Greenpeace did not organise this activity and the climbers are not acting for Greenpeace - they are acting in their own private capacity," climate and energy campaigner, Amanda Larsson said in a statement.
"Nick Hanafin and Siana Fitzjohn have both been involved in Greenpeace protests over the years, but this occupation of the OMV oil rig is an Extinction Rebellion activity."
The Extinction Rebellion is described as a grassroots environmental movement, with no clear legal structure.
Hope said someone had assisted the protest, including those who transported them into place.
"If it's not the organisation that enabled and facilitated them to go there, who owns the boat? There is an organisation then enabled them to get to the rig."