Rep. Frank Wolf, R-Va., asked President Obama to fire his ambassador to Vietnam for failing to defend an American citizen under detention in the authoritarian state and “misleading” Congress about his human rights advocacy as ambassador.

Wolf recounted, for the president, the story of Dr. Nguyen Quoc Quan — a Vietnamese-American “arbitrarily detained” in Vietnam on April 17 and still imprisoned. “Only at my urging did Ambassador Shear initiate contact with Mrs. Ngo to update her on her husband’s situation,” Wolf told Obama. “But even more troubling is the fact that Dr. Quan is an American citizen, and yet there appeared to be little urgency to securing his release.”

Quan is a California resident and pro-democracy activist. The state arrested him on charges of terrorism.

Wolf also took Shear to task for going back on his promise to host an Independence Day celebration on July 4 at the American embassy for human rights and democracy activists in the country.

“Late last week it was brought to my attention that many of the most prominent democracy and human rights activists in Vietnam were not invited to the event,” Wolf wrote. “I called him directly this morning to find out if the embassy had invited the dissidents as had been agreed upon. His response was appalling. He said that he had invited a few civil society activists but then said that he needed to maintain a ‘balance.’”

Wolf suggested Obama replace Shear with a Vietnamese-American who understands the country and “not be tempted to maintain smooth bilateral relations at all costs.”