The Southeast Asian nation's first civilian leader in decades has faced international condemnation for a lack of moral leadership regarding the Rohingya, victims of what the UN views as a campaign of ethnic cleansing.
Senate Majority Leader Mitch McConnell, a longtime Suu Kyi friend and ally, said that during a telephone call she "agreed with the need for immediate and improved access of humanitarian assistance to the region, particularly by the International Red Cross, and she conveyed that she is working toward that end."
A crackdown by Myanmar's army, launched in response to attacks by Rohingya militants on August 25, has sent nearly 400,000 refugees from the stateless Muslim minority fleeing into neighboring Bangladesh. Hundreds have been killed.
Suu Kyi, who is the de facto head of government in the nation also known as Burma, said it was important that violations of human rights be addressed, the Kentucky Republican said on the Senate floor.
The longtime human rights icon and Nobel peace laureate has been berated for failing to speak up for the Rohingya minority amid a crisis that has shocked the international community.
McConnell warned against "unfounded criticism" of Suu Kyi, noting that she has no command over the powerful military which ran the country for 50 years.
"In my view, publicly condemning Aung San Suu Kyi, the best hope for democratic reform in Burma, is not constructive" and could slow the progress toward a representative government, McConnell said.
Last week US senators including John McCain introduced a resolution condemning the violence and calling on Suu Kyi to act.
McCain has sought to remove language from a defense spending bill detailing expanded military cooperation with Myanmar.
