Bill de Blasio, the New York mayor, has said he may order the removal of the city's landmark statue of Christopher Columbus amid national soul-searching over the removal of Confederate-era monuments.

The statue, which is the centrepiece of the city's famed Columbus Circle, was commissioned in 1892 to commemorate the 400th anniversary of Columbus landing in the Americas.

It has been suggested by local government officials in several US cities that monuments to Columbus should be taken down because of the explorer's brutal treatment of indigenous communities.