The condolences were addressed to the Communist Party of Viet Nam (CPV) Central Committee, the National Assembly and Government of Viet Nam, and the Viet Nam Fatherland Front Central Committee.
The Central Committee of the Lao People's Revolutionary Party (LPRP), the Lao National Assembly, the President of Laos, the Lao Government, the Central Committee of the Lao Front for National Construction (LFNC), and the people of Lao ethnic groups expressed the deep condolences over the passing of the Vietnamese Party leader.
Viet Nam has lost a steadfast revolutionary leader; and the Party leader's passing away is big loss to the Party, State, people of Vietnam and his family, the message wrote.
It further said that throughout his revolutionary career, he devoted all his energy and intelligence to important works in the cause of national liberation and reunification, and the renewal of the Communist Party of Viet Nam (CPV), especially the Party building and rectification, as well as in the fight against corruption and other negative phenomena, helping Viet Nam continuously develop, thus raising the country's position in the international and regional arena.
Comrade Nguyen Phu Trong has become an outstanding leader of the era. The Party, State, and people of Laos have lost an extremely close and dear comrade.
He is a revolutionary leader in the new era, a successor of President Ho Chi Minh, making great, valuable and important contributions to strengthening and nurturing the great friendship, special solidarity and comprehensive cooperation between the two Parties, States and peoples of Laos and Viet Nam.
"We believe that the Party, State and people of Viet Nam will turn this loss into solidarity strength, continue moving forward, building Viet Nam into an industrialized and modernized country, and achieving the target of rich people, a strong country, and a fair, democratic, and civilized society," it said.
Meanwhile, in its condolence message, the Communist Party of China (CPC) Central Committee said the Chinese Party and people have lost a good comrade, a good brother, and a good friend.
With immense grief, it extended the deepest condolences and sincerest sympathies to the CPV Central Committee, the Vietnamese State and people.
The Vietnamese Party leader was a staunch Marxist and a great leader of the CPV and the Vietnamese people. He dedicated his entire life to the cause of his Party and nation, making outstanding contributions to Viet Nam's Doi Moi (renewal), the cause of building socialism in Viet Nam as well as the socialist movement in the world, the message said.
He was a close comrade and a sincere friend of the CPC and the Chinese people. He inherited and developed the traditional comrades-plus-brothers friendship between the two Parties and two countries, and forged a profound friendship with the CPC and Chinese leaders, it added.
The Vietnamese Party leader and his Chinese counterpart Xi Jinping have jointly elevated the China-Viet Nam relations to a community with a shared future that carries strategic significance and vigorously promoted the continuous development of the China-Viet Nam comprehensive strategic cooperative partnership. The CPC, the Chinese government and people will always miss comrade Nguyen Phu Trong.
The CPC said it believes that CPV and the Vietnamese people will turn grief into strength, carry on the legacy of comrade Nguyen Phu Trong, stay united and strive to make new and greater achievements in the cause of Doi Moi and socialism building.
China and Viet Nam are socialist neighbors connected by mountains and rivers and a community with a shared future that carries strategic significance.
China has always regarded Viet Nam as a priority in its neighborhood diplomacy and stands ready to work with Viet Nam to continuously consolidate political mutual trust, strengthen solidarity and cooperation, and step up the building of this community to benefit the two peoples and contribute to promoting peace and development in the region and the world, the message said.
In his letter of condolences, President of the Cambodian People's Party Samdech Techo Hun Sen showed his sadness at Party General Secretary Trong's passing away, which he described as a great loss to the CPV, the Vietnamese State and entire people.
The legacy of comrade Nguyen Phu Trong, a clear-minded leader who devoted his entire life to the struggle for Viet Nam's independence and for peace and prosperity of the Vietnamese people will be remembered by many generations, stated Hun Sen.
The CPP leader underlined that through his leadership, the Party General Secretary has reinforced the friendship and brotherhood with Cambodia and, for years, strived to enhance the close cooperation not only between the CPP and CPV but also between the two Governments and peoples.
Hun Sen extended his deep and sincere condolences to the bereaved family.
In his letter, Cambodian Prime Minister Samdech Thipadei Hun Manet wrote that Party General Secretary Nguyen Phu Trong devoted his whole life to the revolutionary cause of the CPV and peace, development, and prosperity of Viet Nam.
Viet Nam has lost an outstanding leader, and Cambodia has lost a good friend who always strived to contribute to the Viet Nam-Cambodia brotherly relationship, he stated.
Mourning the Vietnamese Party leader, President of the Cambodian National Assembly Khuon Sudary described Party General Secretary Nguyen Phu Trong as an outstanding leader, with profound vision and great dedication, who had a great impact on Viet Nam's socio-economic development and institutional modernisation.
His passing away leaves a great loss not only to Viet Nam but also to everyone who had the honor of knowing him, Khuon Sudary wrote.
"We are extremely grateful for Party General Secretary Nguyen Phu Trong's continuous dedication in promoting the strong relationship between Viet Nam and Cambodia as well as his important role in bringing the two countries closer together," she stated.
Expressing his deepest condolences, Russian President Vladimir Putin noted that comrade Nguyen Phu Trong dedicated his whole life to his Fatherland.
Through the many years working in important positions of the State and Party, comrade Nguyen Phu Trong received high respect from Vietnamese people and had a great reputation in the international arena.
Russia will remember the CPV General Secretary as a true friend who made great personal contributions to the establishment and development of the comprehensive strategic partnership between Russia and Viet Nam, Putin said.
"I had an opportunity to meet that wonderful person many times and will forever remain impressed," he wrote, extending his sincere condolences and encouragement to the bereaved family and the entire Vietnamese people.
In her letter of condolences, Valentina Matvienko, Speaker of the Federation Council of the Federal Assembly of the Russian Federation, described Party General Secretary Nguyen Phu Trong as a big friend of Russia, an experienced political activist, and a famous State leader; and highlighted his contributions to the reinforcement of the comprehensive strategic partnership between Viet Nam and Russia as well as bilateral cooperation.
The letter of Chairman of the State Duma of Russia Vyacheslav Volodin read that it is difficult to fully appreciate the great contributions by comrade Nguyen Phu Trong to strengthening the friendly relations between Russia and Viet Nam.
On behalf of the National Duma deputies of the Russian Federation, he extended his condolences to the bereaved family.
General Secretary Nguyen Phu Trong passed away due to old age and serious illness at 1:38 p.m. on Friday in Ha Noi, aged 80. Viet Nam's Party Central Committee, National Assembly, president, government, and Central Committee of the Viet Nam Fatherland Front will issue a special announcement on the organization of a state funeral./.