Chicken meat samples sent by a Chinese supplier to US fast-food chain KFC meet the national standard after testing, the Department of Agriculture in North China's Shanxi province said.

Media reports said last month that the Suhai Group, a KFC supplier based in the province, adds toxic chemicals to feedstuff to make chickens grow faster — 45 days for a chick to grow large enough for slaughter.

The reports said the feedstuff Suhai prepared was so toxic it could kill flies. Suhai denied the allegations.

On Tuesday, the Department of Agriculture in Shanxi said samples of feedstuff and chicken meat from Suhai meet national standards, China News Service reported.

The report said testing was carried out by the Shanxi Entry-Exit Inspection and Quarantine Bureau and Shanxi Feedstuff and Veterinary Drug Inspection Institute.

The province's agriculture department said in a statement that chickens raised by the Suhai Group were white- feathered birds imported from the United States.