Seoul, Mar 25 (IANS): North Korea restored some personnel to an inter-Korean liaison office in its border city of Kaesong on Monday, South Korea's Unification Ministry said, just three days after Pyongyang withdrew all its staff from there.

Four or five North Korean officials returned to the office earlier in the day and held a meeting with their South Korean counterparts, Yonhap News Agency quoted a Ministry official as saying.

"The North Koreans said that they came down (to the liaison office) to take their shift as usual.

"Accordingly, the representatives of liaison officers (of the two Koreas) held a meeting in the morning and plan to operate (the office) as usual," the official said.

"They said that the North's commitment remains unchanged for the liaison office to carry out projects in line with the North-South joint declarations," he said, apparently referring to the agreements that their leaders reached in their three summits last year.

The official however, cautioned that it remains to be seen whether the operation of the liaison office has fully returned to normal as the number of North Korea officials sent there is just half of the ordinary level.

Earlier Monday, South Korea also sent its officials to the liaison office, hoping to normalise the communication line as soon as possible and keep pushing for planned projects with North Korea, such as video reunions of families separated by the 1950-53 Korean War.

On March 22, North Korea abruptly pulled its staff from the liaison office, saying that the decision was based on an order from "higher-ups". It did not provide clear reasons for the withdrawal.

The two Koreas opened the office last September to foster their cross-border exchanges and reduce tensions by keeping a communications channel open at all times.

It was a follow-up to an agreement their leaders reached in April.

They agreed to hold a weekly meeting between the office's co-heads to discuss pending issues, but since the breakdown of last month's summit between North Korean leader Kim Jong-un and US President Donald Trump, no such meetings have been held, though Seoul has insisted that there were no problems in communication with Pyongyang.