SEOUL (AFP) - The South Korean government decided on Tuesday to petition the constitutional court to disband a leftist political party branded as pro-North Korean.

The move to try and break up the Unified Progressive Party (UPP) was approved at a Cabinet meeting which agreed that the party's objectives ran counter to the "basic democratic order of the constitution," Justice Minister Hwang Kyo Ahn told reporters.

The Cabinet vote came months after a number of UPP members, including MP Lee Seok Ki, were arrested on charges of plotting an armed revolt in support of North Korea.

Hwang said Lee headed a group that formed the core of the UPP and followed North Korea's strategy to "revolutionise the South".

The UPP reacted by accusing President Park Geun Hye's government of "trampling" over democratic principles.

The party also suggested it was an effort to distract attention from a widening probe into allegations that the domestic spy agency interfered in last December's presidential election.

"This is not only a suppression against the UPP but vandalism against democracy ... The demise of this regime has become inevitable," the UPP said in a statement.