Tkatchenko said in a statement on Friday that he "stood aside" after consulting with Prime Minister James Marape, who would assume the portfolio.
"I want to make sure the recent events do not interfere with the official visits and summits we are going to have with all the World Leaders in the coming weeks," Tkatchenko said
"I also want to ensure the truth of this matter is cleared and the misinformation and lies are corrected," he added.
RNZ Pacific reports US President Joe Biden, New Zealand Prime Minister Chris Hipkins and Indian Prime Minister Narendra Modi are due on 22 May for a historic visit.
Government House official secretary Bill Toraso on Wednesday denied media reports that the governor general's office had spent 3 million kina (US$825,000), but confirmed to Reuters 10 of its staff had travelled to London, in addition to 10 guests.
Two foreign ministry officials also traveled with Tkatchenko, who had been asked by Marape to represent PNG in his place.
Media and online news sites in PNG, a Pacific island member of the Commonwealth, have been running hot with insults and criticism of the cost of travel since Saturday's Coronation in London's Westminster Abbey, with many saying the money would have been better spent on hospitals.
Tkatchenko's daughter, who accompanied him on the trip has become a focal point for anger, after a social media account in her name discussed luxury shopping before boarding a flight in Singapore.
Earlier on Friday, Marape said Tkatchenko had apologised to the people of PNG for remarks he made to the Australian state broadcaster, in which he called people criticising his daughter on social media "primitive animals".
Marape said he was also offended by the remarks.
Papua New Guinea Foreign Minister Justin Tkatchenko has stepped aside. Photo: Facebook / Hon Justin W Tkatchenko MP