Syngenta AG responded to U.S. lawmakers' concerns over the seed and pesticide giant's takeover by China National Chemical Corp, by saying the acquisition doesn't raise "any food safety or significant national security issues."

Switzerland-base Syngenta responded on Thursday after four senators representing farm states sent a letter to the U.S. Treasury Department requesting that the Treasury-led Committee on Foreign Investment in the US (CFIUS) look at the proposed $43 billion deal's potential impact on the US food system.

The senators said that increased foreign control over important parts of US food production could create threats to domestic food security. Syngenta generates 27 percent of its sales in North America, according to the company.

Paul Minehart, a spokesman with Syngenta, said in a statement that the company would "welcome a full review" of the deal by the U.S. government.

"We do not believe the proposed transaction raises any food safety or significant national security issues," he said. "The proposed combination with ChemChina is good for farmers and customers in the US and all over the world."

In their letter on Thursday, Senate Agriculture Committee members Chuck Grassley and Joni Ernst from Iowa, Debbie Stabenow from Michigan, and Sherrod Brown from Ohio requested a formal role for the U.S. Agriculture Department and the Food and Drug Administration in the CFIUS review.

The Syngenta acquisition was announced in February. It is the latest acquisition in the agriculture sector by a Chinese company after the 2013 purchase of Virginia-based Smithfield Foods. That deal was reviewed by CFIUS and other agencies and approved.