WASHINGTON - Bill Richardson, the former U.S. ambassador to the United Nations and a frequent emissary in hostage negotiations who has worked to secure the releases of WNBA star Brittney Griner and another jailed American, Paul Whelan, visited Moscow this week and held meetings with Russian leaders, a person familiar with the matter said Tuesday night.The visit came as American officials have continued to press Russia to release Griner, who was sentenced last month to nine years in prison in a drug possession case, and Whelan, a Michigan corporate security executive serving a 16-year sentence on espionage-related charges.
The U.S. government regards both as wrongfully detained.MORE: Lawyers for Brittney Griner appeal Russian prison sentenceSecretary of State Antony Blinken announced in July that the U.S.
had made a "substantial proposal" to Russia to facilitate a swap. Though he did not detail the terms, a person familiar with the matter said the U.S.
had offered to release convicted Russian arms dealer Viktor Bout.MORE: Dennis Rodman says he received permission to go to Russia to advocate for Brittney Griner's release from jailPaul Whelan and Brittney Griner ((Photo credit KIRILL KUDRYAVTSEV/AFP via Getty Images and The Washington Post via Getty Images)In an interview with The Associated Press last month, Richardson said he was hopeful about the chances of a two-for-two prisoner swap.