The rival parties have finally struck an eleventh-hour deal on redrawing the electoral map, dispelling concerns about a possible delay in the coming April general election.

The ruling Saenuri Party and the main opposition Minjoo Party of Korea agreed Tuesday to increase the share of representative seats in the 300-seat National Assembly from 246 to 253, while reducing that of proportional ones from 54 to 47.

They also agreed on redistribution of the parliamentary seats among provinces and major cities based on population density. The populous capital zone -- encompassing Seoul City and Gyeonggi Province -- saw their combined seats increase by 10, while provinces with low population density -- including North Gyeongsang and South and North Jeolla -- lost seats.

Based on the accord hammered out by the two parties, the special redistricting committee under the National Election Commission is expected to finalize the new constituency map by Thursday, with the National Assembly scheduled to vote on it Friday.

The legal deadline for redrawing constituency boundaries was Nov. 13, five months ahead of the April 13 vote. The long delay in rezoning electoral districts has created a mess.

With the old constituency map became invalid on Dec. 31, all electoral districts suddenly disappeared in Korea, a situation totally unimaginable in a democratic country where power changes hands through the ballot box.

Under the election law, it is illegal for candidates to engage in campaign activities when the boundaries of their electoral districts are not fixed. This means all campaign activities since Jan. 1 were illegal, as they were staged in the absence of a legitimate electoral map.

This put the NEC and the prosecution in a serious dilemma. As law enforcement agencies, they were supposed to strictly crack down on illegal campaign activities. But had they done so, they would have faced outrage from candidates. So they chose to let candidates engage in campaigning, even though it was illegal in principle.

The main culprit behind the whole mess was partisan politics. The rival parties could not see the common good beyond partisan interests. Now, they should learn a lesson. They should ensure that the task of redrawing electoral boundaries is not held hostage to partisan interests any more.

In fact, the two parties at first delegated the job to an independent committee under the NEC. But the panel could not act independently as its members were picked by the political parties. 

From now on, the task of selecting the members of the panel should be left entirely to the NEC to ensure its genuine neutrality and independence. The relevant regulation needs to be revised to ban the involvement of political parties.

Now the NEC has to rush to prepare for the election. The two parties themselves are pressed for time to select candidates. The NEC and all political parties need to do their utmost to make sure that the April election is held without a hitch.