South Korean trade negotiators are expected to be on the defensive as they meet with their U.S. counterparts on Friday to renegotiate a bilateral free trade agreement.

President Donald Trump's administration is looking to reduce the U.S. trade deficit with Seoul, which stood at $3.5 billion in the third quarter, according to U.S. data. South Korea, on the other hand, is worried about the political ramifications of folding to Washington's demands.

It's imperative that the outcome of renegotiation works in the national interest of each country, said Wendy Cutler, a former acting deputy United States Trade Representative who was the chief U.S. negotiator for the deal, known as "Korus."

The White House, she told CNBC, "should not only focus on what it wants, but also see what it can do for Korea because for a negotiation to be successful, both countries need to win."

Trump threatened last year to scrap the seven-year-old accord unless it were revised, but South Korean President Moon Jae-In was initially opposed to changes. Analysts say he changed his mind to avoid destabilizing the bilateral relationship as both countries work together on reigning in North Korea. Washington and Seoul, alongside Tokyo, play critical roles in containing Pyongyang's nuclear and missile program so strained ties between any of the three nations could disrupt international efforts in containing the rogue state.