Aiyar also said he was "deeply disappointed" that an "intelligent" man like Tharoor should want to rush to judgment in this manner and come out with this effusive remarks.
"This kind of chameleon like praising just after a few days(after Modi coming to power) is uncalled for. It demonstrates great immaturity," Aiyar told NDTV.
In a surprise praise for Modi, Tharoor had yesterday said from the AICC podium that the opposition would be "churlish" in ignoring the voices of inclusive outreach of the new Prime Minister.
The former Union Minister had also held that the "accommodative and inclusive language should be welcomed and it would be churlish to ignore that".
"This kind of chameloon politics is utterly undesirable," Aiyar said, adding," I am very very sad that he should have created this controversy at this stage."
Aiyar said it is his job as a member of the Opposition to keep "red alert" on a man whose past record does not inspire confidence in him.