British drugmaker GlaxoSmithKline (GSK) is investigating alleged corruption by staff at its pharmaceuticals division in Iraq, the group announced on Monday.

GSK, which already faces a bribery probe in China, stressed that it would not tolerate illegal behaviour by staff.

"We are investigating allegations of improper conduct in our Iraq business. We have zero tolerance for unethical or illegal behaviour," a spokesman told AFP.

London-listed GSK employs fewer than 60 people in its pharmaceuticals operation in Iraq, while the allegations relate to a "small number" of individuals, he added.

"However, we are investigating whether there has been any improper conduct and these investigations are ongoing."

The Wall Street Journal had reported on Monday that a person familiar with GSK's Middle Eastern operations had emailed the drugs firm to report alleged misconduct and corrupt practices in Iraq dating from 2012 and 2013.

The spokesman added on Monday that GSK remained committed to improve healthcare in emerging nations like Iraq.

"Operating in emerging markets is challenging given the issues many of these countries face with funding and maturity of their respective healthcare systems," he said.

"However, we continue to believe that with robust compliance systems and, by working closely with local governments, our presence in these markets can help improve access to medicines and broader healthcare."

GSK is currently in the process of overhauling how it markets and sells products around the world, he added.

"We ... continue to make fundamental reforms to our sales and marketing practices.

"Following successful roll out in the USA, we are globally changing how our sales representatives are paid and we are also stopping the practice of paying doctors to speak on our behalf.

"We believe these changes will eliminate any perception of conflict of interest and ensure incentives for our employees are aligned with the best interests of patients."

On Friday, GSK revealed that it had dismissed a small number of workers at its Chinese division as part of the routine monitoring of travel expenses.

However, the move was not linked to Beijing's ongoing bribery probe, the spokesman said.

In July 2013, GSK admitted that senior employees at its China business appeared to have breached Chinese law, after authorities alleged that employees had bribed government officials, pharmaceutical industry groups, hospitals and doctors to promote sales.