The far-right extremists aboard vessel aiming to 'defend' Europe from migrants and refugees were confident of resolving technical difficulties Defend Europe

Volunteers on a German refugee rescue ship have been deployed to help a vessel chartered by far-right activists that became stranded in the Central Mediterranean.

Sea-Eye said Italian officials told their crew that the C-Star, operated by an anti-immigration group calling itself Defend Europe, had suffered a mechanical failure and could not manoeuvre.

A spokesperson for Sea-Eye, which is among those Defend Europe has accused of "colluding" with Libyan people smugglers, said it was prepared to offer any aid needed.