New Delhi- Prime Minister Narendra Modi today hailed the first International Yoga Day as a "new era of peace", moments before he surprised thousands in New Delhi by taking to a mat himself to celebrate the ancient Indian practice.

Yoga-loving Modi led more than 35,000 people, including bureaucrats, students and soldiers, performing poses such as the half camel and cobra in a 35-minute mass outdoor yoga session beginning at 7:00 am (0130 GMT) on a New Delhi boulevard.

Organisers are hoping the event qualifies for the Guinness Book of World Records for the largest yoga class at a single venue.

The current title, according to the Guinness website, was set by 29,973 students in Gwalior, India, in 2005.

"Yoga is more than only physical fitness. We are not only celebrating a day but we are training the human mind to begin a new era of peace," Modi told the crowd at Rajpath avenue.

He thanked the United Nations and the 177 co-sponsoring countries for adopting his idea for a world Yoga Day. Modi then surprised the crowds by leaving the stage, removing his glasses, and securing a spot at the front of the massive session to mirror the stretches, breathing, and meditative moves beamed on giant screens along the historic avenue.