India's capital will turn into a virtual fortress for US President Barack Obama's visit this weekend. Prime Minister Narendra Modi, Obama and other dignitaries from the world's two largest democracies will attend Republic Day celebrations on January 26, which include a military parade and display of weaponry.

A no-fly zone with a radius of 400 km will be established, covering cities such as Jaipur and Agra, and extending to the border with Pakistan.

India Republic Day
An eagle flies amid contrails from Indian Air Force planes during a full dress rehearsal for the Republic Day parade in New DelhiAdnan Abidi/Reuters
India Republic Day
India's Border Security Force Daredevils motorcycle riders take part in a full dress rehearsal for the Republic Day parade in New DelhiAdnan Abidi/Reuters
India Republic Day
Indian soldiers march during a full dress rehearsal for the Republic Day parade in New DelhiAdnan Abidi/Reuters
India Republic Day
Adnan Abidi/Reuters
India Republic Day
Adnan Abidi/Reuters
India Republic Day
Adnan Abidi/Reuters
India Republic Day
The Indian Army's BrahMos weapon systems are displayed during the dress rehearsalAdnan Abidi/Reuters
India Republic Day
The Indian Army's Pinaka multi-barrel rocket launcher systems are displayed during a full dress rehearsal for the Republic Day paradeAdnan Abidi/Reuters

On-the-ground security has been beefed up, with extra police patrols and checks at metro stations. Snipers will be deployed at more than 70 high-rise buildings around central Delhi.

Obama will be accompanied by First Lady Michelle Obama on his three-day trip and is expected to travel in 'The Beast', his heavily-armoured limousine. They plan to tour the Taj Mahal.

It may not rain on Obama's parade, but, judging by the smog and fog cloaking the Indian capital during rehearsals over the past few weeks, visibility could be a problem.

In 2010, the event was wreathed in thick fog that obscured the view for the guest of honour, the then president of South Korea.

India Republic Day
Band members of the Indian security forces rehearse for the Republic Day parade on a cold winter morning in New Delhi, on January 6, 2015Anindito Mukherjee/Reuters
India Republic Day
Members of the security forces rehearse for the Republic Day parade amid dense fog in New Delhi on January 2, 2015Anindito Mukherjee/Reuters
India Republic Day
Soldiers march during a rehearsal for the Republic Day parade on January 16, 2015Ahmad Masood/Reuters
India Republic Day
Indian soldiers are silhouetted against a traffic light as they prepare to rehearse for the Republic Day parade on January 8, 2015Adnan Abidi/Reuters
India Republic Day
Band members of Indian security forces rehearse for the Republic Day parade on a foggy winter morning in New Delhi, January 8, 2015Adnan Abidi/Reuters
India Republic Day
A member of the Border Security Force Daredevils motorcycle team performs during a rehearsal for the Republic Day parade on a foggy winter morning in New Delhi, January 8, 2015Adnan Abidi/Reuters
India Republic Day
An Indian Air Force soldier walks past the India Gate in New Delhi during a rehearsal for the Republic Day parade on December 30, 2014Ahmad Masood/Reuters
India Republic Day
Members of the Presidential Guards rehearse for the Republic Day parade on a foggy winter morning at Rajpath in New Delhi on January 8, 2015Chandan Khanna/AFP