Dr Williams, who is in the country for the All Africa Bishops' Conference, described his visit to the paediatric ward as "inspirational".

But he was told that the unit, which has cared for thousands of the country's sickest children over the years, faces imminent closure as Mildmay International, the British NGO that runs it, cannot afford to do so for much longer.  The 33-bed specialist HIV paediatric unit - known as Elizabeth Ward - is expected to close down in just 37 days when the existing funds run out.

Speaking after the visit, the Archbishop said: "It's been an inspirational experience this afternoon.

"I have seen how much real future is being offered especially to the children here, the generosity and imagination of the work - the quality of care is really wonderful to see.

"And of course when people see that there is hope like this, then it helps them to be honest about themselves and face their conditions.

"I really hope and pray there will be resource to keep this level of care, love and professionalism going on.

"I know that there are many problems that organisations like Mildmay face especially with the work of children and I really, really honestly want to see this work continue and hope that generous people will go out to support it.

"It is crucial for the life of this country and this continent."

The children who come to Elizabeth Ward are often perilously close to death. "They are very, very sick as a result of their HIV – with severe malnutrition, pneumonia, tuberculosis, septicaemia," says Harriet Nakanja, a nurse at the centre, which is run by British NGO Mildmay International.

The flagship 33-bed specialist HIV paediatric in-patient unit, which for more than a decade has cared for thousands of the very sickest children affected by HIV in the East African nation, is facing imminent closure. Existing funding runs out on September 30, and with no immediate prospect of new money staff are getting ready to shut it down.

"Keeping this unit open is incredibly important to us," says Fi McLachlan, Mildmay International's chief executive. "In many ways it is a unique facility, certainly in Uganda and East Africa.

To donate to the unit, or for more information about it, visit www.mildmay.org or call their fundraising team on 020 7613 6311