South Korean Prime Minister Lee Nak-yon tweeted a congratulatory message Tuesday before attending Emperor Naruhito's enthronement ceremony, held before an audience of roughly 2,000 domestic and international guests.

"I congratulate the start of the Reiwa Era," he tweeted.

Lee's visit to Japan comes amid a recent deterioration of bilateral ties over wartime history and trade policy and is being closely watched to see if it leads to improved relations.

"I'll meet with Prime Minister Shinzo Abe as well as other political and economic leaders so that conversations between South Korea and Japan could be accelerated," Lee said.

The prime minister also offered condolences for the victims of Typhoon Hagibis, which triggered massive flooding in Japan and killed more than 80 people earlier this month.

Lee told reporters after the ceremony that he felt the "solemnity of Japan's history and culture."

Other Asian neighbors marked the occasion with congratulations, expressing hope for good relations.

"We hope that both countries' relations will continue to develop in a healthy manner," China's Foreign Ministry spokeswoman Hua Chunying said at a regular news conference.

Relations between China and Japan have been improving recently, with the two sides preparing for President Xi Jinping's first state visit to Japan planned for next spring.

The Philippine government conveyed its "warm wishes" for the Reiwa Era under the emperor's "ideals, wisdom and benevolence."

The office of Philippine President Rodrigo Duterte said in a statement that Manila is "confident that this historic occasion will bring new momentum in further strengthening of an already excellent Philippines-Japan relationship."