A cruise ship with 206 people on board ran aground in northwestern Greenland on Tuesday.
With the closest Danish Defence ship over 2,000km away at the time of the incident, help is not expected to arrive until Friday evening.
“Our units are far away, and the weather can be very unfavourable,” said Cmdr Brian Jensen of the Joint Arctic Command.
On Wednesday, a research ship owned by the Greenland government unsuccessfully attempted to pull the ship off ground during high tide.
No one on board the cruise ship is in danger and no damage has been reported, authorities said. However, three passengers on board the ship are reportedly isolating with Covid-19.
When will cruise passengers be rescued in Greenland?
The Australian-operated, Bahamas-flagged cruise ship - Ocean Explorer - has 206 passengers and crew aboard.
When it ran aground, the closest Danish navy ship was about 1,200 nautical miles (more than 2,000 kilometres) away, according to Jensen. It is heading to the site and is expected at the grounded ship by Friday at the earliest.
The Joint Arctic Command is a joint operational territorial command of the Danish Defence operating in Greenland and the Faroe Islands. As well as protecting the sovereignty of the Kingdom of Denmark in the Arctic Region, it carries out search and rescue missions, research and pollution prevention tasks in the region.
Jensen said in a statement there is no immediate danger to human life or the environment, but that officials "take this incident very seriously”.
The 104.4-metre-long and 18-metre-wide Ocean Explorer ran aground on Monday in Alpefjord in the Northeast Greenland National Park. It's the world’s largest and most northerly national park and is known for icebergs and the musk oxen that roam the coast.
The ship belongs to Ulstein Group in Ulsteinvik, southern Norway.
Are any other ships helping with the rescue?
Authorities have been in contact with another cruise ship in the area and it had been asked to remain nearby to assist should the situation develop. The other cruise ship was not identified.
The grounded cruise ship might also get free on its own when the tide is high, Greenland television KNR reported, though recent attempts by a Greenland research vessel to help free the ship failed.
"Regardless, the most important thing for us is that everyone gets to safety,” Jensen said.
“There are still no reports that human life or the environment is in acute danger," Joint Arctic Command added on Tuesday.
'A difficult situation'
In an update on Wednesday, Joint Arctic Command said that it has sent personnel from the Sirius Dog Sled Patrol on board the grounded cruise ship, who gave assurance that the crew and passengers of Ocean Explorer are in "good condition". If needed, Sirius personnel can reach the accident site within an hour and a half.
"The crew and passengers are in a difficult situation," they added, "but after the circumstances, the atmosphere on the ship is good and everyone on board is fine.
"There are no indications that the ship has suffered serious damage from the foundation."
An inspection vessel is still heading towards the cruise ship, where it is still expected to arrive on Friday evening.
The primary mission of the Joint Arctic Command is to ensure Danish sovereignty by monitoring the area around the Faeroe Islands and Greenland, two semi-independent territories that are part of the Danish realm.