Phil Robertson, deputy Asia director for Human Rights Watch, praised Surin as “still the only Asean secretary-general who actually understood and promoted a people’s Asean even if the national government leaders didn’t understand or want that vision”.
Robertson ended his social media tweet with the comment that Surin was “a man who still had much to do”.
Patrick Murphy, the US Deputy Assistant Secretary of State for Southeast Asia, also expressed his grief.
“Dr Surin Pitsuwan was a great statesman, humanitarian, educator, and family man. Among his many contributions were strengthened US-#Thailand ties,” Murphy said through his Twitter account. "It was an honour to call him a friend.”
Diplomats in Thailand from the US the United Kingdom, Sweden, Canada and Australia among other nations also joined in the mourning.
“He made many contributions to the stability and prosperity of Thailand and the region throughout his distinguished career,” said US Ambassador Glyn Davies in a statement.
Davies also recalled his personal moment with Surin back in January last year, when they visited an Islamic school in Surin’s hometown, Nakhon Si Thammarat. "As Dr Surin took me around his school with great pride, the joy on students’ faces when he greeted them was moving and impressive," the envoy added.
“A great man, a believer in multilateralism and in forging close ties within Asean,” said Canadian Ambassador Donica Pottie.
“A Statesman who still had much to give – huge loss to Thailand and region,” said British Ambassador Brian Davidson.
Vidar Helgesen, Norwegian Climate and Environment Minister, wrote admiringly of Surin in a tweet: “Devastated to learn about the untimely passing of Surin Pitsuwan. A brilliant mind, a fine man, a true friend.”
Muhammad Chatib Basri, a former finance minister of Indonesia, wrote: “He was a great man. Big loss for all of us. I was with him at Harvard last October. We strolled around at Cambridge Common Park.”