By David Morgan

WASHINGTON (Reuters) -U.S. Senate Majority Leader Chuck Schumer will push to include in upcoming defense policy legislation a bipartisan amendment to sanction China over its alleged role in producing the synthetic opioid fentanyl, he said on Sunday.

Schumer blamed China for much of the fentanyl that U.S. authorities say is responsible for the overdose deaths of tens of thousands of Americans. He said the drug comes from production sites in China "with the total acceptance and acquiescence of the Chinese government."

"I will push an amendment - bipartisan - into the defense bill that will include major fentanyl stopping and sanction empowering legislation, and we will bring that bill to the floor this week," Schumer told a news conference in New York.

"I hope it will pass. I believe that will pass with strong bipartisan support. And it should. It must."

The Chinese embassy in Washington, D.C., was not immediately available for comment.

Beijing has accused Washington previously of using the fentanyl crisis as a pretext for imposing sanctions on Chinese companies and has offered to work with other nations to tackle drug problems.

Chinese state media have repeatedly described addiction and demand for the drug as U.S. domestic problems.

Schumer said the amendment, proposed by Democratic Senator Sherrod Brown and Republican Senator Tim Scott, would authorize the White House to declare fentanyl trafficking a national emergency and open the door to sanctions.

"This will really get tough with them and we will make them clamp down on the fentanyl coming to the United States," Schumer said.

Legislation introduced by the two lawmakers this year would require U.S. President Joe Biden to sanction key members of international criminal organizations involved in fentanyl trafficking and allow proceeds from sanctioned property to fund law enforcement.

The Democratic-led Senate is due to begin debating the fiscal 2024 National Defense Authorization Act, or NDAA, on Tuesday. The Republican-controlled House of Representatives passed its own version of the bill on Friday.

The legislation, which sets policy for the Pentagon, is expected to face an unusually contentious path to becoming law this year, after the House added a number of amendments on "culture war" issues including abortion and transgender services that Democrats oppose.

The Senate is expected to pass its version of the NDAA this month, after which the two chambers will negotiate a compromise that would come up for votes later in the year.

(Reporting by David Morgan; Editing by Josie Kao)