US FDA accuses Ranbaxy Laboratories of fraud, concealment and selling substandard drugs

Mamoru Tsunoda, spokesman for the Japanese drug maker, said the firm is closely watching the development and it is too early to say whether the firm would walk out of the deal.

"We would like to continue our work until the deal is closed while also keeping close eyes on what's going on between Ranbaxy and FDA," he said. However, the Japanese firm is expected to go for stringent due diligence before it goes ahead with the transaction.

A Ranbaxy spokesman said the company strongly denied any wrongdoing and would file a response in the court on Monday.

"An investigation has been underway for approximately three years. Despite this, no charges have been filed. During this period, Ranbaxy has been cooperating fully with the Department of Justice. We've been conscientious in trying to provide information to the government," the spokesman said.

"We deny the allegations contained in the motion, but will cooperate with the inquiry," he said.

"The United States Food and Drugs Administration has verified over 200 random samples of various products marketed by the company in the US and all were found to be complying with all the specifications as per the filing. We remain committed to providing high quality generic medicines at affordable prices to our customers and patients in the United States," he added.