The launch of a satellite to monitor Earth's gravitational field, scheduled for Wednesday from a base in northern Russia, has been postponed to October 5 because of technical problems, the European Space Agency (ESA) announced on Monday.

Launch preparations at the Plesetsk cosmodrome 800 kilometres (500 miles) north of Moscow were stopped on Sunday "due to an anomaly in one of the units of the guidance and navigation subsystem of the launcher's upper stage," ESA said.

Fixing the problem will mean separating the rocket's components to replace the unit, it said in a press release.

The launch has been rescheduled to October 5 at 1421 GMT, ESA said, adding, "The satellite and its mission will not be affected by this launch delay."

The one-tonne satellite is called the Gravity field and state-steady Ocean Circulation Explorer, or GOCE.

It is part of ESA's "Earth Explorer" programme, initiated in 1999, to deepen understanding about some of the fundamentals of the planet -- its atmosphere, oceans, biosphere and interior.

GOCE's launcher is a Rockot, a derivative of a Russian intercontinental ballistic missile operated by a joint venture between EADS Astrium and the Khrunichev Space Centre.