In Africa, the announcement was met with a mix of enthusiasm and caution.

The restitution of 26 objects to Benin “does not change the policy of the British Museum, nor legislation in Great Britain,” said Hartwig Fischer, the director of the London institution, which has 73,000 objects from sub-Saharan Africa in its collections, many obtained in colonial times. The museum has been in a decades-long dispute with Greece over the so-called Elgin marbles, which came from the Parthenon, and the governor of Easter Island requested last week the return of Hoa Hakananai’a, a statue that is among the British Museum’s most popular items.

Mr. Fischer said that while the British Museum’s trustees were open to all forms of cooperation, “the collections have to be preserved as whole.”

He recognized that Mr. Macron’s announcement would “intensify the debate” about access, and would contribute to “the next dimension of cooperation” as African countries develop their cultural and museum infrastructure.

Hartmut Dorgerloh, the director of the Humboldt Forum in Berlin, a giant museum of non-Western art set to open next year, said in an interview that Mr. Macron’s pledge to return the 26 objects had made issues of Africa’s heritage “more obvious, more visible and also more urgent.” In the future, he said, European museums would “have to return” objects in some cases, while in others, the inclusion of artifacts in collections would have to be viewed as “the result of European or global history.”