The decision to repatriate the wooden tabot comes as a growing number of museums worldwide have begun discussing steps to repatriate artworks looted during the colonial era.
The Ethiopian artefact is one of a number taken by British soldiers at the battle of Magdala in 1868.
The tablet features a carved inscription symbolically representing the Ten Commandments and the Ark of the Covenant -- the container said to have been used to carry the commandments down from Mount Sinai by Moses.
The tabot is currently sealed inside an altar at Westminster Abbey.
All Ethiopian churches have a covered tabot which is considered sacrosanct and can only be seen by the priest.
The governing body of Westminster Abbey had "decided in principle that it would be appropriate to return the Ethiopian tabot to the Ethiopian Church", a spokeswoman said.
"We are currently considering the best way to achieve this, and we are in ongoing discussions with representatives of the Ethiopian Orthodox Tewahedo Church," she said, adding that it was a "complex matter, and it may take some time".
In 2021, a collection recovered from Britain, Belgium and the Netherlands including a ceremonial crown, an imperial shield, a set of silver-embossed horn drinking cups, a handwritten prayer book, crosses and a necklace was returned to Ethiopia.
Most of the items were plundered by the British army after it defeated Emperor Tewodros II in the Magdala battle in what was then Abyssinia.
Ethiopia hailed the repatriation of those artefacts as being of "huge significance".
A small but increasing number of pieces have been returned to their countries of origin in recent years.
In 2022, the museum service in the Scottish city of Glasgow returned six items looted from temples and shrines in northern India in the 1800s.
Over 70 pieces -- including 12 Benin bronzes -- were returned to Nigeria in 2022 by the Horniman Museum in London while Germany and France have also returned bronzes.
California's Fowler Museum earlier this month returned seven royal artefacts to Ghana while in January London's British Museum and Victoria and Albert Museum (V&A) also give back gold and silver artefacts looted from Ghana's Asante royal court.
The abbey's decision will put pressure on the British Museum to reconsider its position on the 11 tabots which it holds, according to a report in The Art Newspaper industry journal.
