Beijing, Jan 9 (IANS): North Korean leader Kim Jong-un returned home on Wednesday from Beijing by train, concluding a surprise visit that sparked expectation of a second summit with the US on denuclearising the Korean Peninsula.

Kim's armoured train departed from Beijing at 2.08 p.m., according to South Korea's Yonhap news agency.

The Chinese Foreign Ministry did not confirm the information on Kim's journey but said it would issue an official press release.

Kim is expected to reach the North Korean capital on Thursday, reports Efe news.

As on previous occasions, Kim's agenda has not been made public, but he is reported to have held a summit with Chinese President Xi Jinping on Tuesday.

Yonhap reported that on Wednesday, Kim visited the facilities of a Chinese traditional medicine firm for close to 30 minutes, after which he had lunch with Xi.

This was Kim's fourth visit to China in the last year and came amid reported preparations for a second meeting between Kim and US president Donald Trump to resume denuclearization talks.

The first meeting between Kim and Xi in Beijing took place ahead of North Korea's participation in the Winter Olympics held in South Korea, which kicked off a process of rapprochement between the two Koreas.

The other two summits with Xi in May and June occurred soon after his meetings with South Korean President Moon Jae-in and with Trump in Singapore.