South Korean and Romanian leaders pledged on Tuesday to boost defence industry cooperation as Seoul pushes to establish itself as the world's fourth-largest arms exporter amid reports of huge additional contracts in the works. President Yoon Suk Yeol hosted his Romanian counterpart, Klaus Iohannis, for a summit and pledged to increase cooperation in the defence industry, including joint production of weapons, a statement said. South Korea's defence minister Shin Won-sik separately hosted Poland's deputy defence minister, Pawel Bejda, amid reports of an impending contract for Hanwha Aerospace to supply additional weapons systems and negotiations over financing.