SEOUL: Six North Koreans who were rescued on Saturday drifting at sea off the east coast were sent back to the North on Wednesday after Pyongyang did not respond to repeated attempts to communicate, South Korea's Unification Ministry said.

The six had been questioned by a team of officials about their wish to be repatriated, the ministry which handles ties with the North said earlier this week.

Such questioning by South Korean authorities is routine when North Koreans are rescued at sea.

The six North Koreans were on two fishing vessels, but one was damaged beyond repair and they were returned on the remaining vessel, a Unification Ministry official said by telephone, asking not to be named.

The South Korean government tried to reach the North through the liaison office in the Panmunjom truce village on the border but the North did not respond, the official said.

The South also attempted communication through the UN Armistice Commission and then broadcast the intention to repatriate the six through loudspeakers at the border, Unification Ministry spokesman Lee Duk-haeng told a briefing.

The rescue comes as South Korea's new liberal government has pledged a more moderate approach to North Korea including engagement and reopening a communication channel that has been severed amid tension over Pyongyang's arms programmes.

A guide vessel from the North received the six North Koreans when South Korea led their vessel to the maritime border off the Korean peninsula's east coast earlier on Wednesday, the ministry officials said.

South Korea imposed unilateral sanctions against the North after its fourth nuclear test and a long-range rocket launch last year, in addition to sanctions applied in 2010 after the sinking of a South Korean navy ship that Seoul blamed on the North.

North Korea denied involvement in the sinking.

The sanctions cut off almost all exchange between the rival states that had been set up since 2000, when South Korea's "sunshine policy" brought a period of cautious rapprochement.