A recent Al Jazeera documentary, Trail of the Dove, revealed a $100 million secret fund and special surcharges and commissions used by BAE to facilitate what was the biggest arms deal in British history.
BAE Systems and its predecessor, British Aerospace, earned over $80 billion in 20 years from a series of sales to Saudi Arabia known as al-Yamamah (the Dove).
In January, Britain's attorney general said the decision to stop the investigation was "an uncomfortable one."
Anti-fraud officials had been investigating allegations that BAE ran a "slush fund" offering incentives to Saudi officials in return for lucrative contracts.
The OECD's anti-bribery division asked Britain last December for an explanation of its decision to halt the corruption inquiry into the sales.
UK 'shortcomings'The OECD said on Wednesday it welcomed the explanations given, but said it remained unconvinced that London had acted in accordance with the OECD anti-bribery convention and was worried by shortcomings in British law.
Angel Gurria, the secretary-general of the OECD, told reporters in Brussels that the statement was important because it was made by other industrialised nations - "the peers of the UK government".
"It is up to each country's commitment to the rule of law to pursue those infractions," he said, speaking at the margins of a World Bank/OECD anti-corruption conference hosted by the Belgian government.
"The great question is how will that be picked up in the UK itself and what will the authorities do about it? That is where the great responsibility lies," Gurria said.