Democratic Party of Korea Chairman Lee Jae-myung speaks during the party's Supreme Court meeting, at the National Assembly on Wednesday. (Yonhap)

Main opposition leader Lee Jae-myung on Wednesday resumed his duties as the Democratic Party of Korea chairman, two weeks after being injured in a knife attack on Jan. 2.

Lee kicked off his return by presiding over the party’s Supreme Council meeting in the morning.

The chairman referred to the upcoming April parliamentary election as an opportunity to pass judgment on the current administration’s performance.

“The upcoming election will work as a midterm evaluation ... on the current administration and its power,” Lee said in an opening speech for the Supreme Council meeting.

“The Democratic Party believes that the current administration has failed to live up to the expectations of the Korean citizens in terms of performance and outcomes over the past two years,” he added. "It is why we believe we must hold (the administration) accountable."

Lee blamed the current administration for “the struggling economy, the escalating security threats surrounding the peninsula and the deteriorating livelihoods of the people.”

Before the Supreme Council meeting, Lee told reporters as he arrived at the National Assembly that “what he has experienced is trivial compared with the pain people feel around the world due to real hardships.”

He pledged to fulfill his responsibilities as the party chairman and expressed gratitude to all those who helped him in his recovery.

During Lee’s two-week absence, several nonmainstream Democratic Party lawmakers announced their departures from the party, citing disagreements with the current chairman and his stranglehold on power.

Former Prime Minister and ex-Chairman of the Democratic Party Lee Nak-yon has created the most buzz among such lawmakers, as he gears up to launch his own political party. The ex-premier officially left the Democratic Party last week after Lee Jae-myung turned down his request that he step down from his role as chairman.

At an event held to welcome newcomers to the party at around noon, Lee Jae-myung expressed regret concerning the ex-premier’s latest moves.

“Unfortunately, former Prime Minister Lee Nak-yon alongside a few other lawmakers have left the party, despite existing efforts to unify the party,” Lee Jae-myung said. “Regardless, I believe it is our duty and calling to forge new paths and present new hopes for the people in one spirit.”

Lee’s return to the Assembly comes as the Democratic Party faces several hurdles that stemmed from the two-week leadership void.

On top of several heavyweight politicians leaving the main opposition party, the ruling People Power Party has managed to regain some measure of voter support.

A poll conducted by Realmeter on 2,508 respondents aged 18 or older last week showed that support for the ruling party notched up 3 percentage points on-week to 39.6 percent. The figure marked a 10-month high for the ruling party.

While the Democratic Party remains more popular with a rating of 42.4 percent, it shed 2.1 percentage points on-week in the cited period.

“The recent nationwide campaign trail led by People Power Party interim Chairman Han Dong-hoon and his mentions of the need for the revival of the first lady’s office has led to an increase in the ruling party’s popularity,” Realmeter explained.

“The Democratic Party, meanwhile, saw a slight decline in its support due to the noise within the party regarding its questionable choices on election candidates, coupled with the decision of several (lawmakers of the) anti-Lee Jae-myung faction to leave the party.”

Lee Jae-myung was stabbed in the neck by a 67-year-old man -- whose name is being withheld by police -- on Jan. 2 while on a visit to a construction site for a new airport located near Busan. The assailant later confessed to police that he stabbed Lee to prevent him from becoming president.

Lee was initially airlifted to a hospital in Busan, but was then relocated to Seoul National University Hospital. Lee was discharged from the hospital last week after undergoing surgery for a laceration to a major vein in his neck.