WASHINGTON (Reuters) - A Democratic senator on Thursday urged President Barack Obama to use U.S. trade laws to restrict "surging" imports of solar panels from China.

"The American solar industry is facing unparalleled challenges and without the leadership of your administration this industry may disappear leaving behind additional workers without employment," Senator Ron Wyden said in a letter.

"Letting that happen is unacceptable."

The plea came just days after solar panel maker Solyndra LLC filed for bankruptcy, becoming the third U.S. solar firm to succumb to pressure from China in recent weeks.

Solyndra said it had been unable to bring down its costs fast enough to compete with cheaper panels from China, despite receiving more than $535 million in federal loan guarantees.

"Chinese imports of solar panels are surging and are on pace to increase 240 percent this year, compared to 2010. Furthermore, imports of Chinese solar panels increased 1,593-percent between 2006 and 2010," Wyden said.

The Oregon Democrat said the Obama administration had "ample tools" to restrict the imports, including the possible use of anti-dumping or countervailing duties.

The administration should also consider an emergency safeguard tariff, such as Obama successfully imposed on tires from China two years ago, he said.

"Furthermore, China's subsidization of solar panel production provides the grounds for your Trade Representative to pursue litigation at the World Trade Organization.

"I urge you to work with the domestic industry and to quickly use these authorities to prevent an industry from being decimated by unfair, foreign competition," Wyden said.

(Reporting by Doug Palmer; Editing by Sandra Maler)