Commissioned by the ministry, ADPI is reportedly in the final stages of deliberation on the final candidate, evaluating some 30 categories, including airport operation, adjacent development, construction cost and environmental impact.

Two candidate sites -- Miryang, a city 386 kilometers southeast of Seoul, and Gadeok Island close to the country's largest port city of Busan -- have been vying for selection.

Informed government sources said the announcement will likely be made early next week, given Minister of Land, Infrastructure and Transport Kang Ho-in is scheduled to attend the inauguration of the Panama Canal's expansion on June 26 as a special envoy of President Park Geun-hye.

The ministry will choose a candidate at any cost this time without postponing or shelving the project, they said.

With the selection in the offing, both sides are engaged in a heated war of words, claiming superiority.

Daegu, Ulsan and the North Gyeongsang Province support Miryang as the candidate site for the new airport, citing excellent accessibility and economic feasibility.

Busan, the country's largest sea port and No. 2 city, wants the airport to be built on Gadeok Island, not far from the existing Gimhae International Airport, saying it could be operated around the clock and expanded if necessary.

Politicians from both ruling and opposition parties have weighed in on the divisive issue.

Busan-based lawmakers from the ruling Saenuri Party have vowed not to accept the decision if Miryang is chosen. Saenuri lawmakers who are in favor of Miryang criticize them for "trying to apply pressure on the government."

The main opposition Minjoo Party of Korea has been largely supportive of Gadeok Island. Former party leader Moon Jae-in recently visited the island, suggesting he supports the location.

The presidential office is taking a wait-and-see approach on the touchy issue.

Observers said politicians should stay away from the issue, arguing their intervention could "distort the fairness and validity of the site selection and sow conflict among the public.

In 1992, Busan raised the need for a new airport in the southeastern part of the country to replace Gimhae International Airport on the western outskirts of the city. The administration of late President Roh Moo-hyun, who served as the chief executive for five years from February 2003, embarked on reviewing the project.

As a campaign promise for the 2007 presidential election, then opposition party candidate Lee Myung-bak, pledged to build a new airport. His government ended up scrapping the plan amid bitter rivalry between residents and politicians in March 2011, citing both sites failed to meet the requirements for economic and environmental feasibility.

During the 2012 presidential election, President Park Geun-hye, the then-ruling party candidate, vowed to push for the project again. In June last year, the government picked APDI to select a final site. (Yonhap)