Both South Korea and Japan are "vitally important" allies to the United States, the State Department said Monday, stressing that Secretary Rex Tillerson's use of different words to refer to the two allies shouldn't be read into too much.

During last week's visit to Tokyo and Seoul, Tillerson called Japan an important "ally" but South Korea only an important "partner." That has led to some raising questions about whether the top American diplomat puts a greater emphasis on relations with Japan than with South Korea.

"I wouldn't put too much emphasis on a word choice there. Obviously, both are strong allies and partners in the region," State Department acting spokesman Mark Toner said, adding that Tillerson has spoken several times with his South Korean counterpart just as he did with the Japanese foreign minister.

"I don't want to get into any argument over who's more important in this relationship. We consider both vitally important to the United States," Toner said.

Another question that was raised about Tillerson's trip to Tokyo and Seoul was why he had dinner with his Japanese counterpart while in Tokyo but chose not to do so while in Seoul.

Toner said that dinner was simply never scheduled.

"There was never any dinner scheduled. The secretary had very productive, long meetings with his Korean counterparts," he said. "And then I think he ended up having a private dinner with his staff."  (Yonhap)