Attending a parliamentary confirmation hearing in Seoul on June 7, 2017, South Korea's foreign minister-nominee, Kang Kyung-whasays she would seek talks with Japan to reevaluate a controversial deal struck in 2015 over the 'comfort women' issue. [Photo/VCG]

Moon provided a certificate of appointment for Kang at the conferment ceremony, which was held in the presidential Blue House earlier in the day, according to the press release by Moon's office.

The liberal leader, who took office on May 10, nominated Kang as the foreign minister nominee on May 21, but the official appointment was delayed amid strong opposition from the main conservative opposition Liberty Korea Party.

The conservative party opposed Kang's nomination over several controversies, including her false registration of her home address for educational purpose, but about 80 percent of South Koreans trusted Moon's nomination of his cabinet members, including Kang, recent opinion polls showed.

The minor conservative Righteous Party and the centrist People's Party denounced Moon's appointment of Kang despite their resistance, though the appointment is a right given to the president.

The minor progressive Justice Party welcomed Kang's nomination, describing the resistance as "opposition for the sake of opposition."

President Moon said the foreign minister post cannot be left vacant anymore because the South Korea-US summit is around the corner and the Group of 20 summit meeting will come.

Moon was scheduled to leave for Washington on June 28 for his two-day summit meeting with US President Donald Trump from June 29.