The Australian government has asked a Swedish special envoy to raise missing 29-year-old Alek Sigley directly with the North Korean regime.

North Korean state media announced this week that Kent Rolf Magnus Harstedt, a special envoy of the Swedish government, had arrived in North Korea.

He met with the regime’s foreign minister, Ri Yong Ho, and, according to DPRK state media, the two exchanged “opinions on the development of bilateral relations and the present situation on the Korean peninsula”.

The special envoy’s arrival comes following the disappearance of Sigley, 29, an Australian who has been living and studying in Pyongyang since April 2018.

Sigley has not been in touch with friends and family for more than a week, and there are fears he may have been detained by authorities in the repressive state.

The Australian government has not had an embassy in North Korea since 1975, and has been working with Sweden and the UK to try to confirm Sigley’s whereabouts.

On Wednesday the foreign minister, Marise Payne, confirmed the Australian government has asked the Swedes to raise Sigley with the North Korean government.

“One piece of information, which I think is very important in terms of the current discussions, is that Sweden’s special envoy is making a regularly scheduled visit to North Korea this week and, as I’ve said, we’re working very closely with them on this matter and we’re seeking their support to raise this directly,” she said in a radio interview.

“But we keep all our avenues under review, in terms of other options and other countries we might be able to work with to seek information.”

Payne said the government was “very concerned” about Sigley’s welfare.

“He hasn’t been in contact with his family and that is definitely out of character,” she said.

“We are aware of the reports that have suggested he might have been detained by North Korean authorities. We are doing all we can to confirm his location and his welfare [and] are making urgent enquiries with North Korean authorities.

“We have to do that through the Swedish embassy in Pyongyang. They look after consular matters in North Korea on our behalf.”

There has been no confirmation of Sigley’s whereabouts since he was last in contact with family and friends last Tuesday.

“He remains out of digital contact with friends and family, and Australia’s Department of Foreign Affairs and Trade continues to seek clarification as to his whereabouts and welfare,” his family said in a statement last week.

“Alek’s family and friends hope to hear from him soon.”

Sigley had been studying a master’s degree in Korean literature at Kim Il Sung University and runs a tour company that organises trips for foreign students. He first traveled to the DPRK in 2014.

He is believed to be the only Australian living in North Korea.

In March, Sigley wrote for Guardian Australia about his experience living there, saying that as a long-term foreign resident on a student visa he had “nearly unprecedented access to Pyongyang”.

“I’m free to wander around the city, without anyone accompanying me,” he said. “Interaction with locals can be limited at times, but I can shop and dine almost anywhere I want.”