Moscow - Russia's struggling space agency has unveiled a new programme that will see the creation of a replacement for the ageing Soyuz rocket by 2020.

The $70-billion plan published over the weekend on the website of the Russian Space Agency (Roscosmos) also envisions the launch of new unmanned missions to the Moon and beyond.

One of the biggest priorities is assigned to finding a replacement for the Soyuz - the backbone of Russian space travel since its development by Soviet scientists in the 1960s.

Both the rocket and its eponymous space capsule for manned missions have served as humans' main link to the International Space Station (ISS) since the scientific orbiter's launch in 1998.

But an accident with an unmanned Soyuz cargo ship in August 2011 caused delays to subsequent missions and renewed fears about the safety of space travel.

The Soyuz became the world's only manned link to the ISS following last year's retirement of the US space shuttle programme.

The Roscosmos plan called for the introduction of an “energy transportation module with a promising propulsion installation that will be ready for testing by 2018.”

The agency said it intended to “deploy a programme for detailed study of the Moon” and launch a series of unmanned missions for studying its soil samples.

The plan also called for “the development of an entirely new class of interplanetary travel technology and technology (enabling) human activity on the planets.”

Roscosmos has been beset by problems in recent years that saw its satellites fail to reach orbit and a high-profile Mars mission crash back down to Earth.

Experts point to a continuing brain drain from the underfunded agency and a reliance on a vast but ultimately inefficient network of state subcontractors as two factors explaining why Russia is increasingly lagging behind Nasa.

Roscosmos said the 2.1-trillion-ruble ($69 billion) programme will receive both state and private funding that it did not identify. - Sapa-AFP