Newly elected Vice-President Ram Sahaya Yadav took that oath of office and secrecy amidst a function at Sheetal Niwas on Monday.
He is the third Vice-President of the Republic of Nepal.
Janata Samajbadi Party (JSP) leader Yadav was elected as the Vice-President in the election held on Friday for the fourth term.
He will assume the office today itself.
After being elected as the Vice-President, he resigned from the lawmaker and the Janata Samajbadi Party.
Yadav was elected as the Vice-President by securing 30, 328 votes while closest contender Astha Laxmi Shakya of the CPN-UML garnered 16, 328 votes.