MOSCOW - An unmanned spacecraft carrying Russia's first humanoid robot to be sent into orbit failed to dock automatically at the International Space Station on Saturday, in a new setback for Moscow.
The Soyuz craft had to retreat to a "secure distance" from the ISS, Russian news agencies said, quoting the space flight control centre.
RIA Novosti state news agency quoted a space industry source blaming "failings" with the docking system.
The docking had been scheduled for 0530 GMT but a live broadcast of the event on the website of the Russian space agency Roscosmos was interrupted when the Soyuz approached to about 100 metres (100 yards) off the ISS.
An emergency meeting at the control centre was underway to decide whether to launch another attempt to link up with the space station, the agency said Saturday.
The life-size robot named Fedor, short for Final Experimental Demonstration Object Research, is the first ever sent up by Russia.
Fedor blasted off Thursday in a Soyuz MS-14 spacecraft from Russia's Baikonur Cosmodrome in Kazakhstan and was to stay on the ISS until September 7 learning to assist astronauts in the space station.
Soyuz ships are normally manned on such trips, but this time no humans were travelling in order to test a new emergency rescue system.
Instead of cosmonauts, Fedor, also known as Skybot F850, was strapped into a specially adapted pilot's seat, with a small Russian flag in its hand.
"Let's go. Let's go," the robot was heard saying during launch, repeating the famous phrase used by the first man in space Yuri Gagarin.
The silvery anthropomorphic robot stands 180 centimetres (6 feet) tall and weighs 160 kilogrammes (350 pounds).
Fedor has Instagram and Twitter accounts with posts saying it is learning new skills, such as opening a bottle of water. It was to trial those manual skills in very low gravity inside the space station.
"The first stage of in-flight experiments went according to the flight plan," the robot tweeted after reaching orbit.
Fedor copies human movements, a key skill that allows it to remotely help astronauts -- or even people on Earth -- to carry out tasks while the humans are strapped into an exoskeleton.
On the website of one of the state backers of the project, the Foundation of Advanced Research Projects, Fedor is described as potentially useful on Earth for working in high radiation environments, demining and tricky rescue missions.