The family and friends of Melbourne trekker Jordan Yap are desperately appealing for greater official intervention after a private rescue team conducting its largest search operation to date found no sign of the 30-year-old, who has been missing on Peru's remote Cordillera Huayhuash circuit for nearly two weeks.

Yap last made contact with family and friends on 14 September, the day he set out on a planned 10-day solo trek through the Huayhuash mountain range, located approximately 400 kilometres north-east of Lima. He was last seen near the very start of the 120-kilometre high-altitude route through the remote Andes.

A trail of missed connections raises alarm

Concern mounted sharply when Yap failed to make contact on Wednesday — his estimated return date. He also did not check back into the Krusty Hostel in Huaraz, where his luggage remains stored, and missed a scheduled flight from Lima to Cusco on Thursday.

Long-time friend Kevin Nguyen said the silence was deeply out of character for the experienced hiker.

"It's really uncharacteristic of him to not have communicated at any point in his journey if he had the chance to," Nguyen said. "It is a very popular trek, where you might have 200 to 300 hikers and guides per week during the busy season, so it is very uncharacteristic that no one's seen him since day one or day two."

Adding to the worry, Yap misplaced a satellite beacon he had been travelling with just days before departing on the hike, leaving him without the device that would otherwise have allowed his location to be tracked remotely.

He had, however, purchased a GPS watch with offline mapping capability in preparation for the trek — a route he had reportedly been planning for more than a year. "He was telling everyone about how he was ready to go on a big hike like this, really excited," Nguyen said.

Biggest search day yet yields nothing

Rescue crews completed their most extensive day of search operations so far on Sunday morning (AEST), covering multiple trails across the Cordillera Huayhuash circuit without locating any trace of Yap.

His family has hired local mountain rescue organisation Socorro Andino Peruano to lead the search effort. The group has a recent record on the same circuit, having successfully rescued a Canadian trekker from the trail. Loved ones are clinging to hope that the organisation can repeat that outcome.

Nguyen stressed the urgency of the situation: "Time is of the essence … because ultimately, as much as we were saying he's been missing since the 23rd, he's had no contact with anyone since the 14th."

He suggested one possibility for why Yap has not been spotted by other hikers on what is a well-trafficked route: "I know Jordan likes to orienteer and navigate and he's quite an adventurer himself, so I wouldn't be surprised if he tried an alternative route."

Who is Jordan Yap?

Described by those who know him as a very experienced and passionate hiker, Yap had invested significant time and preparation into the Huayhuash trek. The Cordillera Huayhuash circuit is considered one of the most challenging multi-day hikes in South America, demanding technical fitness and experience at extreme altitude in the Andes.

When last seen, Yap was wearing a white jacket, green sunshade sweater and grey pants. He was believed to be carrying a 40-litre hiking bag, a Durston dome tent and hiking poles.

The situation draws a difficult parallel to other cases of individuals reported missing in remote terrain, where survival equipment and preparedness can prove critical to outcomes.

Family calls on Australian government to act

With private search efforts so far proving fruitless, Yap's family and friends are now urging the Australian government to work directly with Peruvian authorities to mobilise additional resources across the rugged region.

The Australian Embassy in Peru is understood to be assisting the family, and the Department of Foreign Affairs and Trade has been contacted for comment.

The appeal for greater government involvement reflects the growing anxiety among those closest to Yap, who note that the window of opportunity in a search of this nature continues to narrow with each passing day.

Anyone with information about Jordan Yap's whereabouts on the Cordillera Huayhuash circuit is urged to contact authorities.