The European Union antitrust regulator said Tuesday it has resumed its investigation into the proposed combination of two major South Korean shipbuilders 16 months after it suspended the probe.

The European Commission plans to finalize the probe by Jan. 20, it said on its website.

"The probe was able to be resumed as we fully answered questions by the EU antitrust regulator," said an official at Korea Shipbuilding & Offshore Engineering Co. (KSOE).

KSOE is the subholding company of the world's largest shipbuilding conglomerate, Hyundai Heavy Industries Group, which operates three shipbuilders, including Hyundai Heavy Industries Co.

The resumption of the investigation is the third of its kind since December 2019, when the bloc's antitrust regulator opened a probe into the $1.8 billion acquisition of Daewoo Shipbuilding & Marine Engineering Co. (DSME) by Hyundai Heavy Industries Holdings Co. (HHIH), the holding company of Hyundai Heavy Industries Group.

The antitrust regulator last stopped the investigation into the deal on July 13, 2020. Prior to that, the regulator had stopped and resumed its investigation two times, respectively, in 2020, citing a lack of data related to the combination.

The deal that would create the world's biggest shipbuilder with a 21 percent market share is subject to regulatory approval by six countries -- South Korea, China, Kazakhstan, Japan, the European Union and Singapore.

As of November, China, Kazakhstan and Singapore have given the green light to the deal.

In 2019, HHIH signed a deal with South Korea's state-run Korea Development Bank (KDB) to take over DSME.

In September, HHIH agreed with KDB to push back the deadline for finalizing a deal to acquire DSME by three months to the end of the year. (Yonhap)