TOKYO: Japan was readying to launch its first cargo spacecraft to the International Space Station on Friday, aiming for a share of space transport after the retirement of the US space shuttle fleet next year.

The Japan Aerospace Exploration Agency (JAXA) plans to launch the unmanned H-II Transfer Vehicle (HTV) atop an H-IIB rocket, which is also on its first flight, at 2:01 am Friday Japan time (1701 GMT Thursday), the agency said.

The rocket will blast off from the Tanegashima Space Center on a southern Japanese island, with the HTV carrying 4.5 tons of supplies including food and daily necessities for the six ISS crew, as well as experiment materials.

Eight days later, in an unprecedented attempt, astronauts will operate a Canadian robotic arm at the ISS to grab the HTV and dock it as the vehicle approaches the station.

The 10-metre (33-foot) long cylindrical vehicle, which cost 20 billion yen (217 million dollars), will deliver the supplies, load waste materials and return to Earth, burning up as it reenters the atmosphere.

Japan has spent 68 billion yen developing the vehicle, which is designed to be modified in future to carry humans.

Japan currently has no spacecraft that can send man into space.

JAXA plans to launch one HTV every year until 2015.

The HTV can carry up to six tons of supplies to the ISS, compared with 7.5 tons for the Automated Transfer Vehicle developed by the European Space Agency, and 2.5 tons for Russia's Progress spacecraft, the Japanese agency said.

The H-IIB is also a new rocket for Japan, developed jointly by JAXA and Mitsubishi Heavy Industries.