Chief Minister K Palaniswami thanked Prime Minister Narendra Modi for selecting Thoppur for this purpose.
"The 750-bed modern facility will be set up at Thoppur near Madurai at an estimated cost of Rs 1,500 crore," Palaniswami told reporters in Chennai.
The institute will also have a teaching facility attached to it with 100 MBBS seats.
The AIIMS was announced for Tamil Nadu in the Union Budget 2015-16 but faced some delays over its location, with demands being made by various sections for it to be set up in different places.
Palaniswami recalled that a central team had earlier visited five locations, including those in Madurai, Erode and Pudukottai districts, before zeroing in on Thoppur.
He assured the Centre of all support from the Tamil Nadu government for setting up the proposed facility.
In a letter to the prime minister, Palaniswami said the late chief minister J Jayalalithaa was very keen that an institution of the stature of AIIMS was established in Tamil Nadu for providing quality medical education, research, and high-end tertiary healthcare in the public sector for the benefit of the poor and middle-class.
Palaniswami said he has directed state Health Minister C Vijayabaskar, Principal Health Secretary, J Radhakrishnan and other senior officials to provide all necessary support to the Centre to facilitate early commencement of work.
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