Across India, tens of thousands of people, including military officials, bureaucrats, politicians, students and even diplomats are taking part in yoga sessions on Sunday.

Prime Minister Narendra Modi, an enthusiastic practitioner of yoga himself lead one such session in the heart of India's capital, New Delhi.

"There will be no part of the world that will be untouched by Yoga today. Yoga is an everyday part of life," Modi was quoted as saying by NDTV news channel.

The federal government has drawn up extensive plans to promote yoga on June 21. Modi had set up a new ministry AYUSH for yoga last year.

AYUSH Minister Shripad Naik said that the day would be celebrated at Delhi's Rajpath, an elegant lawn-bordered boulevard that connects the presidential palace to India Gate, on a grand scale.

"Around 40,000 people will gather to perform yoga together. We have also registered for Guinness Book of World records as it will be one of the biggest achievements of performing yoga at same time with so many people," said Nayak in New Delhi.

But in the birthplace of yoga, the government is being criticised for turning it into a Public Relations exercise.

"I, or anyone else, or Congress party leaders and country's citizens practice yoga at their homes and parks. The chances are that some Bharatiya Janata Party (BJP) leaders have taken this yoga day as a marketing and advertising tool," a leader of India's opposition Congress party, Ajay Kumar.

Soft power of India

In his maiden address to the United Nations General Assembly, Modi pitched the idea for a day dedicated to the ancient Indian discipline, prompting the UN to proclaim June 21 as the International Day of Yoga.

While people in 650 districts across the nation stretch it out, yoga enthusiasts in 192 other countries are also expected to join in the celebrations, including in Britain where mats will be rolled out along the banks of the River Thames.

Hundreds gathered in Malaysia's capital, Kuala Lumpur, to honour the ancient practice, while more than 2,000 yoga enthusiasts struck a pose in the Taiwan's capital, Taipei.

Similar events will take place in the Middle East, Europe and the Americas.

Indian scholars believe yoga dates back 5,000 years, based on archaeological evidence of poses found inscribed on stones and references to Yogic teachings in the ancient Hindu scriptures of the Vedas.

Foreign Minister Sushma Swaraj, who is at the UN's headquarters in New York for the day's launch in Times Square, has called yoga "the soft power of India" that can foster world peace.

(Photos: AP)