NEW YORK.- Daniella Luxembourg, president of the international auction house Phillips, de Pury & Luxembourg, announced her resignation Monday to focus on two new ventures. Luxembourg, who has co-owned the company with Simon de Pury for seven years, is setting up a new private art dealing company called Luxembourg Art and is developing an art fund named ArtVest. Luxembourg said in a statement that her time and energy were spent on "structural business matters" and less and less on the art itself. "Art is my real passion," she said, "and I have decided that I want to go back to focusing on that." She will set up her new art dealing firm in New York, London and Geneva, Switzerland. The ArtVest fund will buy and sell works of art from various disciplines. Phillips, de Pury & Luxembourg has headquarters in New York’s Chelsea district and offices throughout Europe. It specializes in the sale of contemporary and American art, jewelry and photographs. Its new name will be Phillips, de Pury & Co.; no replacement for Luxembourg was announced.