Senior Congress leader Shashi Tharoor on Thursday said he was "appalled by the vicious backlash" over his birthday post for veteran Bharatiya Janata Party (BJP) leader LK Advani.

Taking to Twitter, the Thiruvananthapuram MP wrote: "I am frankly appalled by the vicious backlash against my birthday greetings to LK Advaniji. Has civility disappeared entirely from our political discourse?Gandhiji taught us to respect & honour the humanity in our political opponents. It seems that now makes me a Sanghi sympathiser!"

"In fact Gandhiji taught us to fight the sin but love (&embrace) the sinner. Ahimsa is 'a positive state of love, of doing good even to the evildoer'. While good & evil are Gandhian terms I can’t easily use (most human beings are shades of both), I deplore intolerance on either side," Tharoor added.

Tharoor further said that even though he opposes LK Advani and Prime Minister Narendra Modi politically, he intends to continue to wish them well on their birthdays. "My 40 years of writing makes clear what I believe in. Only those who haven’t read me would call me a Sanghi. My values won’t be discarded 4them," he added.

Earlier on Monday, Tharoor wished LK Advani on his birthday and described him as "a fine human being" and "a gentleman in politics".

"Warm wishes for a fine human being, a gentleman in politics, a leader of wide reading and great courtesy. #HappyBirthdayLKAdvani," he tweeted.