text: The $43bn (£33bn) deal is set to be the biggest ever foreign takeover by a Chinese company.
  The deal was cleared by the Committee on Foreign Investment in the United States (CFIUS) which checks deals for national security implications.
  About a quarter of  Syngenta's sales are in North America.
  China National Chemical Corporation offered $465 per share for Syngenta in February. Syngenta's shares subsequently fell to about 20% below that because of concerns that CFIUS would not clear the deal.
  However, now competition authorities elsewhere are expected to give the deal the go-ahead.
  In a joint statement, Syngenta and ChemChina said: "In addition to CFIUS clearance, the closing of the transaction is subject to anti-trust review by numerous regulators around the world and other customary closing conditions.
  "Both companies are working closely with the regulatory agencies involved and discussions remain constructive. The proposed transaction is expected to close by the end of the year."
  When the deal was announced earlier this year, Syngenta chairman Michel Demaré said that it would help the company's pesticides and seeds business to expand further in China.
  "ChemChina has a very ambitious vision of the industry in the future," he said. "Obviously it is very interested in securing food supply for 1.5 billion people and as a result knows that only technology can get them there."
  The Chinese company owns a variety of businesses, included the Italian tyre maker Pirelli, German machinery-maker KarussMaffei and Israel's biggest pesticides producer.
  The deal would be the second-biggest takeover in the chemicals industry in the past year after the $130bn Dow Chemical-DuPont merger announced last December.
target: Shares in Swiss agribusiness group Syngenta have risen 12% after its takeover by ChemChina was given the go-ahead by a US regulator.