Pharmaceutical giant GlaxoSmithKline is investigating allegations of bribery in Iraq, the latest to hit the British based company which has recently been fielding similar corruption claims against it in China.

The alleged misconduct relates to Glaxo's Mideast business and dates back to 2012. It centres on claims that the company hired government-employed physicians and pharmacists as paid sales representatives in a bid to boost product sales.

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

The allegations relate to a small number of individuals and were investigated as soon as the company became aware of them, the spokesman added.

The latest allegations were revealed by the Wall Street Journal, which said it had seen emails from a person familiar with Glaxo's Middle East operation who had written about alleged bribery in GSK's Mideast operation dating back to 2012.

One of the emails read "I believe GSK practices in Iraq violate the Foreign Corrupt Practices Act and the UK Bribery Act," WSJ reported.

The US Foreign Corrupt Practices Act deals with bribery of foreign officials by US businesses or corporations trading securities in the US.

Glaxo responded with an email saying it was taking the allegations seriously and "the scope of the investigation now covers several countries and business units" in the Gulf and Middle East, according to WSJ.

Glaxo is active in Iraq, the United Arab Emirates, Kuwait, Qatar, Bahrain, Oman, Jordan, Lebanon and Syria. The investigations are ongoing.

It is the second corruption scandal to hit the drug maker's overseas operations in less than a year. In July, Chinese authorities accused Glaxo of paying up to £291m ($482.4m, €351.6m) to doctors and officials in an attempt to get them to use its products.

China said that it had detained four senior Glaxo staff but they have not faces charges yet. GSK acknowledged that some of its staff may have broken the law; the company said it was cooperating fully with the investigation.