title: Obama says several Vietnam activists prevented from meeting him
text: HANOI (Reuters) - U.S. President Barack Obama said several civil society members in Vietnam were prevented from meeting him on Tuesday and that, despite great strides made by the country, Washington still had concerns about the limits it puts on political freedom. Obama said during a meeting with about six activists that there were “significant areas of concern” about political freedom and praised those Vietnamese who were “willing to make their voices heard”. Obama announced on Monday the end of an arms ban on Vietnam, which Washington had long said hinged on the extent to which the country’s human rights record had improved. 