By Timothy Gardner and Ayesha Rascoe

WASHINGTON (Reuters) – President Barack Obama welcomed Singapore’s prime minister for a state visit on Tuesday with a major trade deal and China’s development of islands in the South China Sea at the top of their agenda.

Both the United States and Singapore are signatories to the 12 nation Trans-Pacific Partnership (TPP), which Obama hopes Congress will approve before he leaves office in January.

Obama and Prime Minister Lee Hsien Loong touched on the trade issue at the opening ceremony for Lee’s visit, which is the first official one by a prime minister from Singapore since 1985.

“We stand together for a regional order where every nation large and small plays and trades by the same rules,” Obama said.

Lee said TPP would be a major trading group linking both sides of the Pacific. “Not only will the TPP benefit American workers and businesses, it will send a clear signal and a vital signal that America will continue to lead in the Asia Pacific and enhance the partnerships that link our destinies together,” he said.

The TPP faces a battle in Congress. Some U.S. voters blame trade deals for shutting factories, shipping jobs overseas and favoring corporations over the environment. The deal also is opposed by presidential candidates Hillary Clinton, a Democrat, and Donald Trump, a Republican.

Obama believes the TPP will fix problems in a previous trade deal, the 1994 North American Free Trade Agreement, and will create jobs by allowing people around the world to buy U.S. products. The TPP aims to liberalize commerce in 40 percent of the world’s economy and would be a check against China’s influence in Asia.

Also on the agenda during Lee’s visit will be China’s build up of islands in the South China Sea. China claims most of the energy-rich waters through which trillions of dollars worth of shipping trade passes annually and has been fortifying islands in the sea. Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims there.

China has accused the United States of fuelling tensions in the region with patrols and exercises.

Singapore is not a claimant to the South China Sea, but the tiny city-state has the largest defense budget in Southeast Asia at a time when nations are stepping up their military spending in response to China’s assertiveness in the region.

(Reporting by Timothy Gardner; Editing by Bill Trott)