The American security manufacturer Armor Holdings has paid a $16m (£10m) fine to settle bribery charges.
From 2001 to 2006, Armor Holdings paid a UN official to help it deliver a contract to supply body armour for UN peacekeepers, according to US authorities.
The alleged misconduct happened before the company was acquired by British defence giant BAE Systems in 2007.
BAE said it had "co-operated extensively" in the investigation.
"It is important to acknowledge that all of the matters in question occurred well before Armor's acquisition by BAE Systems," spokesman Brian Roehrkasse told the BBC in an e-mailed statement.
Florida-based Armor Holdings agreed to pay the fines in order to avoid facing criminal prosecution on charges brought by the US Department of Justice and the Securities and Exchange Commission (SEC).
According to the SEC, the firm paid a total of $222,750 in 92 separate payments to an intermediary, with the understanding that some of that would be given to the UN official.
The UN official has not been named publicly. He or she is alleged to have tipped off Armor Holdings about the price competitors were tendering, and to have advised the company how much it should bid in order to secure the contract.
The company made $7.1m in revenue and $1.5m in profit through the UN contract, the SEC said in court filings.
In addition, from 2001 to June 2007, the company paid $4.4m to intermediaries who brokered the sale of its products to foreign governments, then improperly disguised the payments on its books, the SEC said.
With those acts, the SEC said, Armor Holdings violated the US laws prohibiting bribery of foreign officials, as well as record-keeping laws.
"Illicit payments to UN officials are no less reprehensible than bribes to foreign government officials," Robert Khuzami, Director of the SEC's enforcement division, said in a statement.
"The important process of selecting body armour for peacekeepers should not be affected by which company pays the best bribes."