MDMK leader Vaiko on Sunday announced his party's support to DMK in the December 21 by-election for the Radhakrishnan Nagar assembly constituency.

In a statement issued in Chennai, Vaiko said the by-election assumes much significance now as time has come to teach the AIADMK a lesson, since the ruling party is not concerned about the problems of the people.

The Radhakrishnan Nagar seat fell vacant following the death of Chief Minister J. Jayalalithaa on December 5, 2016.

The ruling AIADMK and the DMK have already announced E. Madhusudhanan and N. Marudhu Ganesh, respectively, as their candidates for the R.K. Nagar seat.

Sidelined AIADMK leader TTV. Dinakaran will also be contesting as an Independent candidate.

The Bharatiya Janata Party (BJP), on the other hand, is fielding its spokesperson K Nagarajan.

On Saturday, giving a new twist to the by-election actor Vishal Krishna - popularly known as Vishal - announced his decision to enter the poll fray.

Vishal said he will be filing his nomination papers on Monday.

In a tweet Vishal said he is hoping for a change and the change is inevitable.

The Indian National League has announced support for AIADMK's Madhusudhanan. The DMK has already garnered the support of the Congress, VCK, Manithneya Makkal Katchi and other smaller outfits.

The PMK, the DMDK and Tamil Maanila Congress have decided not to contest the election.