WASHINGTON (AP) — The artist Christo is giving two original collages from his upcoming "Over The River" project to the National Gallery of Art in Washington.Christo visited the museum Tuesday with Secretary of the Interior Ken Salazar to announce the gift. Christo's collages and related works will be on display at the museum through January. The collages will become part of the permanent collection.In a statement, Christo says the gallery houses one of the largest collections of his works.On Monday, the Interior Department's Bureau of Land Management approved his "Over The River" installation. Christo plans to suspend silvery fabric panels for 5.9 miles above the Arkansas River in southern Colorado.The temporary installation is slated for August 2014. Christo began the project with his late wife and collaborator Jeanne-Claude.