Healing differences in Scotland after a divisive referendum that came close to splitting the United Kingdom this year will take time, Queen Elizabeth II has said in her annual Christmas broadcast.

In a speech dedicated to the theme of reconciliation, the Queen on Thursday also celebrated progress towards peace in Northern Ireland, after a broad deal was signed by rival parties this week.

She acknowledged differences of opinion in Scotland after a September vote in which 45 per cent voted to become independent from the United Kingdom, while 55 per cent voted to remain within it.

"In Scotland after the referendum many felt great disappointment while others felt great relief, and bridging these differences will take time," the 88-year-old said.

The monarch recalled a visit to Northern Ireland in June, when she was shown around a prison by a former Irish Republican Army commander in a visit in support of the region's peace process.

"The benefits of reconciliation were clear to see when I visited Belfast," the Queen said in her speech.

"My visit to the Crumlin Road Gaol will remain vividly in my mind. What was once a prison during the Troubles is now a place of hope and fresh purpose; a reminder of what is possible when people reach out to one another."

The Queen spoke on the 100-year anniversary of a spontaneous truce between warring soldiers in opposite trenches in World War I, something she described as a "remarkable" event that showed peace was possible.

"Sometimes it seems that reconciliation stands little chance in the face of war and discord," she said.

"But, as the Christmas truce a century ago reminds us, peace and goodwill have lasting power in the hearts of men and women."

The Queen also paid tribute in her address to the medical staff and aid workers fighting the Ebola epidemic, which has killed more than 7500 people, mostly in Sierra Leone, Guinea and Liberia.

"I have been deeply touched this year by the selflessness of aid workers and medical volunteers who have gone abroad to help victims of conflict or of diseases like Ebola, often at great personal risk," she said.

People caring for the sick or handling the bodies of people infected with Ebola are especially exposed to the virus and 365 healthcare workers have died, most of them local staff.