President Ram Nath Kovind on Tuesday underlined the need for the overall development of the northeastern states and said the region's connectivity with the outside world through air and waterways will be improved.

The President said that as much as Rs 90,000 crore investment was earmarked to link Arunachal Pradesh and other northeastern states through railways. 

He was speaking at the inaugural of the Northeast Development Summit at the Convention Centre here. Over 175 delegates from India and abroad are participating. 

Kovind said that water connectivity in Assam through the Barak and the Brahmaputra rivers had also been undertaken. 

He said he was happy for the fact that a few more airports will be opened in the region and assured of improved border roads and national highways in the region. 

"For a short period in history, the eight north-eastern states were the frontier of India. But they were always in India's heart," he said.

Expressing happiness over the ASEAN countries' participation in the summit, he said leaders of these countries had been invited to the Republic Day function next year. 

Earlier in the day, President Kovind arrived in Imphal amid a shutdown called by insurgents that crippled normal life across Manipur.

Schools, government offices and markets were shut. Very few vehicles plied on the roads. However, all flights operated normally.

The Coordinating Committee, the apex body of the six major insurgent groups in Manipur, have called for a 26-hour strike to protest against Kovind's visit to the state. 

Chief Minister N. Biren Singh said: "President Kovind, three north-eastern Chief Ministers, investors and businessmen from home and abroad were coming to Manipur for the Sangai festival.