The director of New York's Metropolitan Museum of Art said Thursday the famed institution would return more pieces of art to countries that were victims of looting as it joins in efforts to fight international antiquities trafficking.

"You will see and hear from the Met museum not only about more outcomes from our research but actually more restitutions, more returns, and more collaborations with those countries," Max Hollein told foreign journalists.

"We don't want to have any object in our collections that came illegally," said the Austrian art historian, who has headed the Met since 2018.

"In some cases, we are not the proper owner," he acknowledged.

In recent years, the Met and other prestigious museums have agreed to return trafficked works, in particular pieces from countries riddled by conflict from 1970 to 1990.

Under Manhattan District Attorney Alvin Bragg, who has been in office since 2022, more than 1,000 pieces worth $190 million have been returned to 19 countries, including Cambodia, China, India, Pakistan, Egypt, Iraq, Greece, Turkey, or Italy.

In May, Hollein announced the creation of a commission to examine the provenance of certain works among the 1.5 million pieces in the Met's collection.

"We are escalating our investment in the research on our collections and the transparency on the origins of our objects," he said.