Long groomed as his heir to the chief minister's throne and to head the Dravida Munnetra Kazhagam [Images], M Karunanidhi [Images] on Friday appointed his son M K Stalin as the Deputy Chief Minister of Tamil Nadu.

The DMK chief, who appointed his 55-year-old son to be his deputy, entrusted to him the portfolios of Industry, General Administration, District Revenue Officers and Minority Welfare hitherto held by him.

Stalin, who still heads the party's youth wing and had shot to fame after his incarceration under MISA during the 1975 Emergency, will also continue to hold the portfolio of Rural Development and Local Administration, a Raj Bhavan press release announcing his appointment, said.

The elevation of Stalin, who was Chennai Mayor during Karunanidhi's earlier tenure between 1996 and 2001, has been on the cards for quite sometime as Karunanidhi had been having problems after his major surgery for back pain in February last. In his absence, Stalin was the main campaigner for the DMK in the Lok Sabha polls.

His elevation came a day after his elder brother M K Azhagiri [Images] was sworn in as Union Chemicals and Fertilisers Minister in the UPA government.

In a statement, Karunandhi (85) said he was unable to pay full attention to the administration because of his ill health.

'I have to clear not less than hundred files a week. I had discussed the issue with Finance Minister K Anbazhagan and asked him whether he can shoulder some more responsibility. He had also cited health reasons (for not taking up).

'After discussions, it has been decided that I will keep one or two important portfolios and Anbazhagan continue as the Leader of the House in the state assembly. Stalin will be after the two of us,' Karunanidhi said.

Stalin, who was the DMK's Deputy General Secretary, was promoted as party treasurer in June last year, giving him the number three spot in the party hierarchy, after Karunanidhi and another veteran General Secretary K Anbazhagan, who is a year older than Karunandhi.

His elevation is seen as an attempt by Karunanidhi to pave the way for Stalin's succession to the positions held by him.

Stalin had deputised for his father at the swearing in ceremony of the union Council of Ministers yesterday in Delhi [Images]. He bore the brunt of campaigning for the DMK in the just-concluded Lok Sabha polls as Karunanidhi, who underwent a major surgery for his back pain in February last, had been advised against travelling by the doctors.