Chennai, Sep 10 (IANS): President Pranab Mukherjee said on Saturday that India's security challenges go beyond the conventional borders and conventional threats.

He also said that the 21st century was witnessing chaos and asymmetric warfare involving both state and non-state actors.

Speaking at the Officers Training Academy (OTA) after reviewing the passing out parade of the summer term here, Mukherjee said: "Our security challenges in fact go much beyond conventional borders and conventional threats in the international arena,"

These include "a sizeable diaspora to protect in unstable regions in the world, energy security issues and protection of maritime sea lanes", he said.

The President said time and again the country had to turn to its armed forces during times of internal crisis, both man-made and natural.

"All these challenges demand a capable and responsive armed forces to ensure stability and peace, so vital for our country on its path of peace and prosperity for all its citizens," he added.

Mukherjee stressed that more than ever, India requires young men and women to take up the challenge of navigation through troubled waters and work tirelessly even at the risk of their lives for the country.

"The Indian Army represents the Instrument of Last Resort. Always remember that the acme of a great and powerful army does not lie in the power it can unleash but the manner and dexterity with which it does so," Mukherjee said.

He also said more than one billion hopes were pinned on the shoulders of young and brave shoulders when they battle odds that seem insurmountable.

Mukherjee expressed happiness to see Officer Cadets from friendly countries like Afghanistan, Bhutan, Fiji, Papua New Guinea and Lesotho at the function.