* Doctors allegedly offered free samples, travel benefits
* Follows earlier claims of bribes in China, Poland, Iraq (Adds details on allegations, further GSK comment)
LONDON, April 16 (Reuters) - GlaxoSmithKline,Britain's biggest drugmaker, said on Wednesday it wasinvestigating allegations of bribery involving some of its staffin Jordan and Lebanon, following earlier claims of corruption inChina, Poland and Iraq.
"GSK can confirm we are investigating allegations regardingthe activity of a small number of individuals in our operationsin Jordan and Lebanon," the company said in statement.
"We started investigating using internal and external teamsas soon as we became aware of these claims. These investigationshave not yet concluded."
GSK faces its biggest challenge over corruption allegationsin China, where authorities in July accused it of funnelling upto 3 billion yuan ($483 million) to doctors and officials toencourage them to use its medicines in a case that rocked thepharmaceuticals industry.
This month its reputation was placed under a further cloudby claims of similar wrongdoing in Iraq and Poland. Poland'sCentral Anti-Corruption Bureau said on Monday that 13 people hadbeen charged, although GSK said it had found evidence ofmisconduct by only a single Polish employee, who wasdisciplined.
The company said it did not have a systemic issue withunethical behaviour and said the 161 violations of its sales andmarketing policies in 2013 was very similar to rates reported byother pharmaceutical companies.
GSK recently took steps to tighten up its marketingprocedures, including a move to stop the practice of payingdoctors to speak on its behalf and tying compensation of salesrepresentatives to the number of prescriptions doctors write.
The latest allegations about Jordan and Lebanon were firstreported in the Wall Street Journal, which cited emails from aperson who first contacted GSK in December.
The emails alleged that GSK sales representatives bribeddoctors to prescribe drugs and vaccines by issuing free samplesto doctors that they were allowed to sell on.
GSK staff were also alleged to have permitted doctors tobring their spouses on paid-for business trips and speakingengagements that may not have taken place, according to theemails. (Reporting by Ben Hirschler; Editing by Greg Mahlich)