By Sakura Murakami and John Geddie TOKYO (Reuters) -A leadership contest in Japan's ruling party to determine who will take over as prime minister headed to a run-off on Friday, putting a candidate seeking to become Japan's first female premier against a veteran making his fifth leadership bid.

Considered a defense policy expert, Ishiba secured a come-from-behind win against Economic Security Minister Sanae Takaichi, a staunch conservative who hoped to become the country’s first female prime minister.

Ishiba defeated economic security minister Sanae Takaichi in a runoff, after the two won the most votes in the first round in a crowded field of nine candidates.