Sources close to Tharoor said he got a call from the Prime Minister's Office asking him to be present for the swearing-in ceremony at Rashtrapati Bhavan.
Tharoor, who contested from Thiruvananthapuram, won by a margin of nearly 100,000 votes beating Ramachandran Nair of the Communist Party of India (CPI).
(Published 27 May 2009, 09:10 IST)