A US congressman has written to President Truong Tan Sang to express “extreme disappointment” that no political prisoners were included in a mass amnesty granted to mark National Day on September 2.
Some 18,000 convicts were released, the second largest ever, as part of celebrations to mark the 70th anniversary of the declaration of Vietnamese independence.
“It is shameful that citizens who tried to exercise their fundamental rights to freedom of speech, freedom of religion and freedom of association continue to be detained while convicted criminals are released,” wrote Democratic congressman, Alan Lowenthal, in the letter dated September 2.
The congressman represents a district centred on Long Beach in southern California which includes areas with a significant population of Vietnamese residents.
The former psychology professor sits on the House Committee on Foreign Affairs and has been an outspoken advocate of human rights in Vietnam.
He said that the government in Hanoi needed to show it was serious about respecting international standards if it wanted to build better relations with the international community and finalise negotiations for the TPP, the Trans-Pacific Trade Partnership.
He named several individuals in the letter including the blogger, Ta Phong Tan, Pastor Nguyen Cong Chinh and Father Nguyen Van Ly.
Vietnam holds an estimated 200 political prisoners, including bloggers, advocates of religious freedom and other government critics. Many were convicted in rapid trials on charges such as plotting to overthrow the government, engaging in anti-state propaganda and abusing democratic freedoms.
The government denies them any political status and officially regards them as common criminals.
Mr Lowenthal visited Vietnam with a congressional delegation earlier this year.
He said at the time that Vietnam was trying to get a better trade deal with the United States, and better access to the US market, without making reciprocal concessions on human rights.
He said Congress would not support a TPP deal with Vietnam unless progress was made.
The General-Secretary of the Communist Party, Nguyen Phu Trong, spoke of the need to respect human rights during his ground breaking visit to Washington in July. It was the first visit to the White House by a leader of the Vietnamese Communist party.
No prominent government critics and bloggers have been arrested and sentenced so far this year.
Some analysts believe that the authorities in Hanoi are bowing to pressure on human rights as they seek to make progress on the TPP and improve ties with Washington in the face of tension with China.
Others suspect any easing of repression is purely tactical and does not amount to a significant change of policy.
The recent detention, for the first time, of the veteran democracy advocate Nguyen Quang A is seen by some as an ominous sign.
Dr Quang A is regarded as a moderate and consensual figure in the developing civil society movement.
He was held for 15 hours at the airport in Hanoi on the eve of National Day after returning from a tour of the United States.
He was accused by police interrogators of meeting anti-state activists in the US.