New York - A former executive at jeweler Tiffany & Co pleaded guilty Friday to stealing more than US$2 million (S$2.5 million) worth of jewelry from her one-time employer.

Ingrid Lederhaas-Okun, 46, a former vice president of product development, pleaded guilty to a count of interstate transportation of stolen property less than a month after she was arrested in connection with the theft.

Among the items were bracelets, earrings and pendants made of diamonds, platinum and gold.

Under a plea agreement, Lederhaas-Okun, a resident of Connecticut, has agreed to forfeit more than $2.11 million and pay $2.24 million in restitution.

Prosecutors said she had been allowed to check out jewelry from Tiffany for reasons that included showing items to potential manufacturers for cost production estimates.

Rather than bringing the jewelry back, Lederhaas-Okun allegedly would report the items missing or damaged. Prosecutors said Lederhaas-Okun subsequently sold some, if not all, of the items to a jewelry reseller.

After Lederhaas-Okun left the company in February in a downsizing, Tiffany took inventory and found she checked out 165 pieces that had not been returned, according to the complaint filed at the time of her arrest.

While Tiffany conducts daily inventories of items worth more than $25,000, the complaint said each piece was worth under $10,000.

Court documents don't name Tiffany, instead calling it a"international jewelry company based in midtown Manhattan."

But a spokeswoman for the luxury New York store had confirmed at the time of Lederhaas-Okun's arrest on July 2, that it was the one cited in court papers. Tiffany declined comment Friday.

US District Judge Paul Gardephe in Manhattan set sentencing for December 10. Federal sentencing guidelines would place her sentence at 37 to 46 months.