KATHMANDU: United Nations Secretary-General Ban Ki-moon has hailed the role that Nepali Congress President and outgoing Prime Minister Sushil Koirala played during the complex negotiations on the Constitution and the protracted complex transition in Nepal.

The Constitution Assembly, elected for the second time, adopted the new Constitution on September 20 with Koirala as the Prime Minister.

Sending a letter to Koirala on October 13, a day after the new Prime Minister, KP Sharma Oli, assumed the Office of the Prime Minister as Koirala's successor, the UN leader said, "I would like to personally convey my warm appreciation for the role you played as Prime Minister of the Federal Democratic Republic of Nepal. I would also like to thank you for the support you provided to the United Nationsl during your tenure."

"I highly appreciate your leadership, both as Prime Minister and the leader of your party, during the complex negotiations on the Constitution and the protracted complex transition," Ban wrote.

Ban recalled former Prime Minister Girija Prasad Koirala's role in bringing the former Maoist rebels to the peace process and wrote, "I am fully aware of the efforts you have made to carry on the legacy of the late Prime Minister Girija Prasad Koirala, who played a leading role in the 2006 Democracy Movement and in bringing the then CPN-M to the peace process."

"Your contribution to the democratization of Nepal and to the conclusion of peace process was invaluable and highly commendable," he added, expressing his sincere hope that Nepal would find inclusive and durable solutions to the current challenges under the leadership of new leadership.

"Please accept, Excellency, the assurances of my highest consideration."