Countdown began today for the first flight-testing of indigenous cryogenic engine on homegrown rocket GSLV-D3, the success of which would take India into the elite club of space-faring nations with such capabilities.

For the first time, India would be using indigenously built cryogenic stage and engine technology, which is crucial to put communication satellites weighing more than two tonnes into geosynchronous transfer orbit (GTO).

The Indian Space Research Organisation's GSLV-D3 would put in GTO the country's latest communication satellite. The 2,220 kgs GSAT-4 satellite has a seven-year mission life.

The 29-hour countdown began at 11.27 am and "things were progressing as per countdown", an ISRO spokesperson said.

The 50-metre tall GSLV-D3 with GSAT-4 is scheduled to blast off from the Satish Dhawan Space Centre at 4.27 pm tomorrow.

It took nearly two decades for Indian scientists to go in for a home-made cryogenic technology after its bid to acquire cryogenic propellant from Russia in 1992 failed in the face of US opposition.

It did not materialise due to strong US opposition and "technology denial regime of big powers", Director of Satish Dhawan Space Centre M C Dathan said.

"Often in the past, we have purchased completed cryogenic engines from Russia and five of them had been used for our GSLV missions. But we felt that it was important to develop indigenous capability as cryogenic technology is crucial to take our space programme to new heights," he said.

"It was a 'milestone' for Indian space programme in many ways and proved 'our capabilities and reflects our scientists' determination to take up any challenge," he said.

Developed by a dedicated team of scientists of ISRO's Liquid Propulsions System Centre (LPSC) at Mahendragiri in Tamil Nadu, the success of this technology will put the country in the elite club comprising the US, Russia, certain European countries, Japan and China which possess the complex cryogenic technology.