South Korea's trade minister returned home Friday after a four-day trip to the United States meant to secure Washington's support for her campaign to become the next leader of the World Trade Organization (WTO).

Trade Minister Yoo Myung-hee met with US government and business officials and discussed a wide array of bilateral issues, according to the Ministry of Trade, Industry and Energy.

During her stay, Yoo especially focused on winning Washington's support for her bid to become the next head of the WTO.

US support is widely seen as crucial in winning the top post of the WTO as the US is the biggest contributor to the WTO in terms of budget.

Yoo vowed to focus on rebuilding trust in the multilateral trading system by making it more relevant, resilient and responsive, once she gets picked as the new leader.

Yoo is currently competing against candidates from seven countries -- Mexico, Nigeria, Egypt, Moldova, Kenya, Saudi Arabia and Britain. The WTO member countries will provide a maximum of four preferences, after which three candidates will be removed from the list. The global trade body is anticipated to deliver the results of the first round of the selection process later Friday (Geneva time).

After carrying out another round of the process to pick two shortlisted candidates, the final result is widely anticipated to be delivered in early November.

Yoo was appointed as trade minister in February last year, becoming the first woman to be named to the top-ranking position in the 70-year history of the trade ministry.

When asked about the trade row between the US and China, the world's top two economies last month, Yoo did not provide a direct statement but reiterated that she will serve all members of the WTO. Yoo added she holds the same stance over the yearlong trade row between South Korea and Japan.

US President Donald Trump has threatened to leave the global trade organization.

"The United States must be allowed to defend itself against unfair trade practices, and the Trump Administration will not let China use the WTO to take advantage of American workers, businesses, farmers and ranchers," US Trade Representative (USTR) Robert Lighthizer said earlier this week.

The remark came after the WTO ruled that some tariffs imposed by the US against Chinese goods violated rules. (Yonhap)