Tongan officials have warned the death toll from the volcanic eruption and tsunami in the Pacific nation is only set to grow, as damage assessment begins.
As Australia prepares to send more aid to Tonga, authorities have confirmed the first casualty from the natural disaster, British charity worker Angela Glover.
The deputy head of mission at Tonga's high commission in Australia, Curtis Tu'ihalangingie, said it would still be weeks before communication was fully restored in the country.
"Communication is on locally, so people can call one another in Tonga, but can't all internationally, we still have limited access to Tonga," he told ABC Radio on Tuesday.
"We still don't have a direct communication with our government."
All Australians have been accounted for in Tonga following the disaster.
There are normally about 300 Australians living in Tonga, but the number is estimated to be less due to COVID-19.
Mr Tu'ihalangingie said there was still uncertainty about the level of damage to Tonga, but basic supplies were needed.
"At this point (Tonga needs) water and also masks," he said.
"The county was covered with volcanic ash and this is very alarming and dangerous, not only for young children but for everyone."
Australia sent a P-8 plane to survey the damage on Monday, with further support on the way.
Pacific Minister Zed Seselja said critical supplies such as food, water as well as communications and clean-up equipment will be sent over on a C-130 plane once the airport in Tonga is able to reopen.
"There is still a significant amount of ash at the airport. It was hoped the airport might open today, but that's more likely now to be tomorrow," Senator Seselja told the Nine Network.
"We've offered $1 million in assistance at the moment, we're looking to hear back from the Tongan government in some more specific detail."
Initial data from Monday's surveillance flight has come through, with on-ground efforts also being carried out by Tongan authorities.
Further supplies will be deployed to Tonga on HMAS Adelaide as early as Wednesday.
A major underwater telecommunications cable was damaged in the tsunami, and is expected to take at least two weeks to repair.
Senator Seselja said work was under way to get communication access to the Pacific nation.
"We're working with Telstra to try and make sure we can get temporary equipment, so some better on-the-ground equipment can exist."
With Tonga enforcing a strict border measure to help keep coronavirus cases out of the country, there are fears international aid efforts could lead to Tonga losing its COVID-free status.
"As much as we are going to send assistance, we will still need to follow the COVID-19 protocols to keep the people in the population safe, rather than us setting a system and there's a tsunami of COVID hitting Tonga, Mr Tu'ihalangingie said.
"We hope to maintain that and we're very appreciative of the understanding of the Australian government and partners."