South Korea and the U.S. began a final push Monday to bridge gaps in tough free-trade negotiations with just days left to strike a deal before an end-of-month deadline.

South Korean Trade Minister Kim Hyun-chong and Deputy U.S. Trade Representative Karan Bhatia, shaking hands across the negotiating table at a Seoul hotel, began their make-or-break talks aimed at reaching agreements on contentious issues including automobiles and agriculture that have defied solution over almost 10 months of haggling. The agriculture disagreements include differences over U.S. beef exports to South Korea.

The countries have until March 31, or the end of this week, to reach an agreement.

They have been trying since June to strike a deal officials say would boost economic ties between two countries that already do more than US$75 billion in trade.

Protests in South Korea have dogged the process since it began. Opponents fear an influx of cheaper U.S. goods will harm livelihoods and cost jobs.

Seven thousand South Koreans took to the streets of Seoul on Sunday to denounce the proposed deal, culminating with a rally in front of the U.S. Embassy.

Though South Korea is the world's 10th-largest economy, the U.S. economy is as much as 15 times bigger.

The two governments need to wrap up the agreement soon because of the approaching end of U.S. President George W. Bush's Trade Promotion Authority, which allows him to send trade agreements to Congress for straight yes-or-no votes without amendments.

Even if a deal is struck this week, votes to ratify it aren't expected for months. South Korean lawmakers would also need to approve any final deal.