India's attempt to land a robotic spacecraft on the moon ended in apparent failure on Saturday after the Chandrayaan-2 lost contact with mission control during its descent to the lunar surface.

The descent at first proceeded smoothly. But the control room fell silent as the landing craft's trajectory diverged less than two miles from the surface and stopped further communications.

If the landing craft crashed - a technical glitch is also possible - the long wait for India to join a small club of countries to land on the moon continues, despite repeated attempts.

The chairman of the space agency, K Sivan, said the data was being analysed to find out what happened. "Let us hope for the best," said Indian Prime Minister Narendra Modi.

The roughly $140m mission, known as Chandrayaan-2, was intended to study permanently shadowed moon craters that are thought to contain water deposits confirmed by Chandrayaan-1 in 2008.

India's achievements in space have been hailed by Modi as a symbol of the country's rising ambition as a global power.

Even after communication was lost, scientists at mission control chanted "Victory for Mother India" in response to Modi's speech.

The mission lifted off on July 22 from the Satish Dhawan space center in Sriharikota, an island off the coast of the southern state of Andhra Pradesh.