U.S. ambassador at large for international religious freedom, John Hanford, said on Friday concern about religious freedom in Vietnam remained but he hoped talks with the government could produce progress on the issue.
"We continue to have concerns about issues of religious freedom, but we look forward to continued discussions with the Government of Vietnam in order to make progress on these issues," Hanford was quoted as saying in a statement from the State Department.
Hanford left Vietnam on Friday after a week-long visit to the communist country that took him to southern Ho Chi Minh City, formerly known as Saigon, and the provinces of Daklak and Gia Lai in the Central Highlands.
Hanford had "open and wide-ranging discussions with senior Vietnamese Government officials, provincial leaders, religious leaders and third-country diplomats," the statement said. It gave no details of the talks.
The Central Highlands is home to many Protestant ethnic minority people including the Montagnards who fought on the side of the Americans in the Vietnam War. Human rights groups say Protestants face repression.
The envoy, who oversees the State Department's annual world report on religious freedom, had highlighted the group in last year's survey when Vietnam was listed with North Korea, Myanmar, Laos, Cuba and China as among countries that exert authoritarian control over religion.
Vietnam denies the accusation.
Vietnam recognizes six religions, but it insists on vetting the groups' leadership and activities.
Hanford visited Vietnam as a fresh row erupted between the government and the outlawed Unified Buddhist Church of Vietnam, which has made renewed efforts to reassert its legal status, revoked in 1981.
Two of the group's leaders -- patriarch Thich Huyen Quang and his deputy Thich Quang Do -- have been accused of possessing state secrets, a serious crime, and await further investigation by authorities.
It was not clear if Hanford had sought, or was able, to meet Do, who lives in Ho Chi Minh City. U.S. ambassador Raymond Burghardt spoke with Quang this year when he was allowed to travel to Hanoi for surgery.
U.S. lawmakers are considering capping non-humanitarian aid to Vietnam and the United States could impose sanctions if it designates the Southeast Asian country a "country of particular concern."