"I am very much committed to maintaining peace and security and determined at holding Constituent Assembly elections. I will move ahead with this principle," he said.
Addressing the national meeting of his party Nepali Congress's (NC) district presidents here, Koirala, who is also the NC president, expressed his commitment to maintaining the unity of the eight-party alliance.
In addition, he said a republic should be established in the country gradually by removing the king's power.
Koirala said the event of the prime minister receiving the credentials of foreign diplomats, which the king used to enjoy in the past, had indicated that the country was heading towards a republican setup.
He said that any decision on the monarchy -- whether it should be kept or abolished -- should be taken "very seriously."
"Republic cannot be achieved in just a decision -- whether that of mine or any other political parties. It (a republic) can be announced one day after gradually removing the king's power," said Koirala.