SEOUL: Dozens of security guards have been injured in clashes with protesting lawmakers in a dispute which has paralysed parliament for weeks, officials said on Sunday.

Scores of opposition Democratic Party (DP) lawmakers and officials have occupied a main parliamentary hall since mid-December to block a series of controversial Bills, including one to ratify a free trade pact with the US.

About 150 unarmed security guards, acting on the Speaker's order, have intermittently attempted to break up the sit-in since Saturday. Some protesters were frogmarched out but most others remained in place by linking arms.

The scuffles inside the National Assembly building have left 53 security guards injured while one of the DP lawmakers had an arm injury, officials said.

Some 900 riot police stood guard outside, checking every visitor's identification to limit unauthorised access to parliament.

The rival parties have been wrangling over dozens of controversial Bills, including one to ratify the US-South Korean free trade agreement, signed last year, that awaits ratification by legislatures.

The opposition, which has 83 seats in the 299-member legislature compared with the ruling Grand National Party (GNP)'s 172, says South Korea should not ratify the free trade pact before the US Congress does.

Opposition lawmakers and critics, including farmers who fear it will hit their jobs, insist that the deal be given another review.

The GNP sees the pact as necessary to stimulate the slowing economy and argues that approval by Seoul will encourage the US Congress to move faster.

Also controversial is a Bill to allow large businesses and newspapers to acquire controlling stakes in local broadcasters and other Bills over tax cuts for the wealthy, easing regulations on industrial conglomerates' ownership of banks and privatising the state-run Korea Development Bank.

- AFP/ir