PHNOM PENH, Cambodia — Vann Molyvann, an architect and urban planner whose pioneering mixing of modernism with indigenous elements transformed the landscape of Phnom Penh, Cambodia’s capital, died on Thursday at his home in the northern Siem Reap Province. He was 90.

His death was confirmed by his daughter Delphine Vann. He lived near the ancient temples of Angkor, from which he derived inspiration.

Mr. Vann Molyvann was best known for combining modernist principles with ancient motifs, a style that came to be called New Khmer Architecture. He was admired by many Cambodians as an embodiment of integrity and vision in a country where art has often taken a back seat to the upheavals of history.

He remained closely associated with the Cambodia of the 1950s and ’60s, an era of relative freedom and growth that was obliterated by the deadly purges of the Khmer Rouge in the 1970s.