South Korea and Vietnam said on Wednesday they agreed to cooperate closely, after the announcement of U.S. tariffs that pose a major challenge for both economies and for companies like Samsung Electronics with big investments in Vietnam.

South Korea's industry minister Ahn Duk-geun is visiting Vietnam as the two countries scramble to negotiate a reduction of threatened U.S. tariffs of 25% and 46%, respectively, that would otherwise apply in July after a global moratorium expires.

Chinese leader pledges to build strong bilateral relations with Hanoi, rejects protectionism, as he begins Asia tour aimed at projecting Beijing as a stable partner.