By David Loyn BBC Developing World correspondent

A campaign to secure the return of a monument stolen from Ethiopia by Mussolini is gathering strength.

Professor Richard Pankhurst from Addis Ababa University - the most prominent authority on Ethiopian archaeology - will be among those protesting outside the Italian Embassy in London on Wednesday.

"We feel that this is not only robbing Ethiopia of an important antiquity, but it is a European country violating the most elementary principles of international law," he said.

The obelisk was recently damaged by lightning

"This is a disgrace. One feels that the European Union has a rogue state in its midst." Professor Pankhurst says that Ethiopia's claim is different from those of other countries who want their heritage restored.

Unlike Greece's claim over the Parthenon Marbles being held in London, Italy has a legal obligation to return Ethiopian loot after signing a treaty in 1947.

The Axum monument was taken during Italy's brief occupation of Ethiopia before the Second World War, and has stood in the Piazza Porta Capena in Rome ever since.

Italy's continued opposition to restitution appeared to change earlier this year after the monument was struck by lightning.

"Since it has already been damaged we might as well give it back," said Italy's culture minister, Vittorio Sgarbi.

But although the logistics for cutting the monument into manageable pieces and shipping it back on American Transport planes have been worked out, Italy has still taken no action.

Ethiopia is seeking the help of other African states at the inaugural meeting of the African Union in Durban this week.

'Insult'

Professor Pankhurst says that Italy's continuing refusal even to meet the Ethiopian Prime Minister Meles Zenawi means that they are still acting like a colonial power.

"I think they are treating Ethiopia very badly, as a second class country.

"We can no longer give them any benefit of doubt. There is no doubt. It is a question of bad faith."

In Axum the loss is seen as a continued insult. The regional head of Culture and Tourism, Fisseha Zibelo Gkidan maintains the monument is part of the identity of the people of Axum.

Since it has already been damaged we might as well give it back

Vittorio Sgarbi

Axum was once the capital city of an empire ruled by the Queen of Sheba.

Her successors left grand monuments over their burial sites, and it was the grandest of these which Mussolini stole to give his empire some of the feel of the original Roman Empire.

"It is a world heritage site," says local guide Haileselassie Berhe. "The world's heritage must remain where it is so that the world can enjoy it."

This small gesture by Italy could make a huge difference to northern Ethiopia which was once defined only by war poverty and famine.

The potential for tourism is enormous, since Axum also houses the Ark of the Covenant, which Ethiopians believe was brought from Jerusalem by the son of the Queen of Sheba.

But the hole in the ground where one of the finest monuments in north Africa once stood does not entice tourists.