A British teacher trapped in Sudan with her husband and four children is still waiting to hear from the Foreign Office.
Jennifer McLellan, 36, was last known to be in a house near the capital of Khartoum after fleeing conflict between the Sudanese army and Rapid Support Forces paramilitary group.
The latest death toll has tipped over 400, with at least another 3,500 Sudanese injured.
A three-day ceasefire has been agreed, and British military flights are preparing for a "large-scale" evacuation of UK nationals from the country.
Foreign Secretary James Cleverly announced that the operation would begin today after ministers came under pressure to help at least 2,000 citizens.
However, Jennifer's uncle - who managed to make contact with her yesterday - says she is "just one in a long line of people stuck in a terrible situation".
Donald told the Daily Record: "She is literally stuck where she is.
"She managed to get in contact with me on Facebook and said they had managed to get some food and on Sunday but now all the fuel has gone and the banking is down they can’t get anything. They’re left in a pretty dire situation.
“It’s 24 hours to drive to Egypt and they’ve no fuel so it’s not going to happen.
"Their best bet is trying to get in a convoy into Egypt but most of these buses have gone now. It will be hard for them to move across country safely.
"The wee ones thought the guns going off were popping balloons. Jennifer will not move out the house with the kids now. Her husband, Mo, will be going out looking for food.
"There’s going to be a massive humanitarian issue here for everybody. Jennifer is just one in a long line of people stuck in a terrible situation.
"She and the children have been registered with the Foreign Office and they have their address of where they were last night, but no one has been in touch."
Jennifer has been living in Sudan for around 15 years, after meeting her Sudanese husband when he was studying in Glasgow.
The couple had two boys and two girls, aged between two and 15, and Jennifer got a job teaching English at a university.
But the family’s lives were thrown into chaos after bombing and shooting began in the capital, cutting electricity and safe access to food and water for much of the population.
Their loved ones are now fearing for their safety, as they are unable to access cash or fuel to escape.
Donald said: "We need someone to go and get them out. They need boots on the ground. They need humanitarian help.
"My sister is in bits and is sick with worry. They’re all struggling to speak about it because they are so worried. It’s the not knowing."
The family have arranged a safe place in Egypt for Jennifer, her husband and children to stay if they can leave Sudan.
Donald added: "I told her to conserve energy and start rationing and just hunker down and try and rest as much as they can. They don’t now whether they are going to have to get out and walk.
"The malitia are very close to them. With these two factions fighting and resources depleting they will start clearing houses."
RAF flights leaving an airfield outside the capital are open to British passport holders, with priority being given to the most vulnerable.
The Foreign Office told citizens not to travel there unless they are contacted and warned that the ability to carry out evacuations could change at short notice during the "volatile" truce.
A Government spokesperson said: "The safety of all British nationals in Sudan continues to be our utmost priority. We recognise that this is an extremely worrying and distressing situation for those trapped by the fighting.
"We are urgently exploring all routes for British nationals to leave Sudan should they wish to.
"Our advice to British nationals continues to be to stay indoors wherever possible and contact the Foreign Office to register your local and contact details."
Families with children or elderly relatives, or individuals with medical conditions, will be prioritised for the flights.
Only British passport holders and immediate family members with existing UK entry clearance are being told they are eligible.
But nationals have been warned that all travel within Sudan is "conducted at your own risk".
Mr Cleverly said: "The UK Government is co-ordinating an evacuation of British nationals from Sudan.
"We have started contacting nationals directly and providing routes for departure out of the country."
The Foreign Office said other exit routes are being considered, with two British military ships - RFA Cardigan Bay and HMS Lancaster - being lined up for possible evacuations.
A team of British troops is understood to have flown into Port Sudan to check out the options.
US Secretary of State Antony Blinken announced that a three-day ceasefire had been brokered. It would extend a nominal truce over Ramadan that did little to stop fighting but did facilitate some evacuations.
Sir Nicholas Kay, a former British ambassador to Sudan, warned that the situation during the ceasefire remains "precarious".
He told BBC Radio 4's Today programme: "The security situation can change very quickly, the command and control over forces isn't complete and there is no trust between the two sides so they might kick off again."
The former diplomat warned that moving around Khartoum could be "very difficult", with the bridges crossing the Blue and White Nile rivers being controlled by the armed groups.