"As Chairperson of UPA, you have been crossing a number of roadblocks tactfully and facing many hurdles successfully.
As it is often said, obstacles are stepping stones to greater success", Karunandhi said in a message to Gandhi who will turn 67 tomorrow.
The nation "looks up to you only at this critical phase" to provide a secular and stable government at the Centre, he said adding that "despite certain impediments, the achievements of UPA government have been quite impressive".
"The poor and middle classes of people of this country certainly realize your abiding interest in their livelihood and welfare", Karunanidhi said in the message.
Acknowledging that she had received Karunanidhi's greetings, Gandhi thanked the DMK leader, Baalu said.