The United Nations says there is a severe shortage of food and humanitarian supplies as a result of the conflict in Tigray, with more than 90% of the population there in urgent need of assistance.
Following a humanitarian truce agreed between the Ethiopian government and opposition forces earlier this month, the first aid has begun arriving by road to the Tigrayan capital, Mekelle.
13 trucks have arrived safely into #Mekelle. More trucks & fuel will follow in morning. This is 1st humanitarian convoy to arrive into #Tigray region since last Dec.— WFP_Ethiopia (@WFP_Ethiopia) April 1, 2022
Good progress, much more needed - we need daily convoys flowing in safely to meet the needs of 5 million people. pic.twitter.com/A6UV7KuMpe
The Tigray People's Liberation Front (TPLF) welcomed the move as "a step in the right direction" but said there should be "a system in place to ensure unfettered humanitarian access for the needy".
Until the arrival of this first convoy on 1 April, the only aid deliveries since mid-December had been by air.
This is far more costly and delivers only minimal supplies.
"Planes carry less cargo at 25 times the cost of truck convoys" says Samantha Power, of the US International Development Agency (USAID).
During the first week of March, only 100 metric tonnes of humanitarian supplied were transported via air to Mekelle, the regional capital of Tigray, according to the UN, far less than is needed.
About half a million children are estimated to be lacking food in Tigray, including more than 115,000 severely malnourished.
Families are exhausting all remaining means to access food, with three quarters of the population reported to be using extreme coping strategies to survive, the UN says.
"The level of food insecurity is expected to worsen in the coming months as remaining food stocks from the last harvest, which was half of normal year production, get depleted."
What's been blocking overland routes into Tigray?
UN aid agencies estimate that 100 trucks carrying food, non-food items and fuel, are required to the deliver the required aid into Tigray every day.
Until now, the main routes have been blocked due to the ongoing conflict.
Continued fighting in the border region between Tigray and neighbouring Afar province to the east has made that route too dangerous.
Roads from the Amhara region to the south and Sudan to the west have also been closed as opposing militia contest for control of these areas.
There is no access either via Tigray's northern border with Eritrea.
What does the government say?
The Ethiopian government rejects claims that Ethiopia is blocking aid, blaming the TPLF instead.
It says that an aid convoy set off from Semera, the capital of Afar province on 17 March, bound for Mekelle, raising hopes that the main overland route would be operational once again. But the convoy never reached there.
The TPLF has denied government accusations that it is to blame for disrupting the aid.
"At no time before, during or after the fighting have aid trucks been prevented from passing through into Tigray by Tigray forces," it has said.
Fuel scarcity a challenge
In addition to other supplies, availability of fuel has been a key issue.
The government has been restricting movement of fuel into Tigray for many months, which has severely affected the distribution of aid within Tigray.
"With no fuel, even if we can get supplies in, getting them to where they need to go is very difficult, or impossible," says WHO chief Tedros Adhanom Ghebreyesus.
For many months, the Ethiopian government also restricted the movement of medical supplies.
The WHO was however allowed to airlift some supplies in February.
It estimates that 2,200 tonnes of emergency health supplies are needed to respond to urgent health needs in Tigray.
Only 221 tonnes have so far been delivered - just about 4% of what is needed.