U.S. President Barack Obama called his South Korean counterpart Lee Myung-bak Wednesday as the two countries' free trade agreement (FTA) is taking effect midnight March 15.

Obama told Lee that the FTA would boost exports and create jobs and growth "immediately" after its implementation, according to a White House statement.

The U.S. president appreciated his South Korean counterpart's "close cooperation" in making the agreement effective, saying it was a "strong example" of the accomplishments in the bilateral partnership, it said.

The trade pact was signed nearly five years ago by the two governments but had since been strongly resisted by certain interest groups in both countries. The deal was approved by the U.S. Congress last October and by South Korea's parliament last November.

The controversy didn't end in South Korea where the opposition has threatened to repeal it, but supporters of the bilateral deal argued it would create tens of thousands of new jobs and increase the gross domestic product (GDP) in both countries.

"The two countries have made great strides in modernizing our alliance to promote security in the region and in promoting economic growth and trade in the Asia-Pacific," the White House said.

In the phone conversation, Obama also said he was looking forward to his upcoming visit to South Korea in late March and anticipated a successful Nuclear Security Summit to be hosted by Seoul.