THE Reserve Bank of Australia's currency maker, Securency, allegedly bribed Vietnam's central bank governor by paying for his child to attend an exclusive British university.

The bribe is one of several lucrative financial incentives funnelled by the RBA company to Vietnamese officials in return for an agreement that Vietnam would print its currency on Securency's plastic bank note material.

The alleged bribery helped Securency win huge bank note supply contracts in Vietnam, transforming the country's currency from paper to plastic between 2002 and 2009.

The alleged bribery happened under the noses of Securency's RBA-appointed board members, who allowed the company to engage in the bribery-prone practice of paying multimillion-dollar commissions to offshore accounts belonging to middlemen who were hired to win contracts from foreign officials around the world.

None of Securency's former Australian directors have been held to account for the board's failure to prevent Securency allegedly engaging in bribery.

The revelations will increase pressure on the Australian Federal Police to charge the Securency executives behind the Vietnamese dealings in what would be the nation's first foreign bribery prosecution.

Legal sources have confirmed to the Herald that Securency funds were used to pay for the university education of one of the children of Le Duc Thuy, who served as the governor of Vietnam's central bank between 1999 and 2007.

Mr Thuy, who remains one of Vietnam's most powerful officials in his role as chairman of the National Finance Supervision Council, awarded Securency currency contracts worth tens of millions of dollars.

Before becoming the central bank governor, Mr Thuy worked as a close aide to former communist party boss Do Muoi.

The legal sources said some of Securency's senior staff were questioned last year by the Australian Federal Police about the payment of the university fees.

It is understood that a secret Securency slush fund was used to pay tens of thousands of dollars in fees for one of Mr Thuy's children to attend the University of Durham, a top-tier British university.

The slush fund was set up with some of the $15 million in commissions paid by Securency to a Vietnamese middleman, Anh Ngoc Luong, in return for helping win contracts. The commissions were paid by Securency into several bank accounts, including one in Switzerland and another in Hong Kong.

Legal sources have confirmed to the Herald that the AFP suspects the commissions were diverted to Vietnamese officials or their relatives. But the sources said senior Securency executives have privately denied having direct involvement in the payment of any bribes, including the university fees.

Under Australian anti-bribery laws, it is illegal to give a benefit to a foreign official to gain a business advantage.

The RBA's chairman, Glenn Stevens, and the federal Treasurer, Wayne Swan, have refused to order an inquiry to examine whether the Securency board, or the RBA, failed to adequately safeguard the company from engaging in bribery.

The AFP inquiry is only examining whether Securency employees engaged in bribery. Securency's chairman between 1996 and 2008 was the former RBA deputy governor Graeme Thompson.