Chief migration officer Solomon Kantha said that Greens politician Nick McKim placed undue pressure on a junior immigration officer and ignored protocols. Kantha said McKim had failed to seek formal approval, instead demanded entry.
McKim said he sent an email to an immigration official and he regarded that as a "formal" approach.
"It is regrettable that he appears to have attempted to circumvent the processes that are known to him and in doing so, placed undue pressure on a junior ICA (Immigration and Citizenship Authority) officer who was simply performing their duties," Kantha told The Australian newspaper.
"Mr McKim has demonstrated a flagrant disregard for PNG and contempt for the organisations he claims to represent," Kantha said.
Kantha said McKim had been issued a visitor visa on entry to the country and was not an official visitor.
"Mr McKim would be aware that all persons seeking entry to a centre must seek appropriate authorisation," he said. "He has done this in the past and access has been approved. However, in this instance, Mr McKim has simply attended the gates and demanded entry," Kantha said.