Europe's far right has lost one of its biggest champions with the defeat of Hungary's nationalist leader Viktor Orban in Sunday's election.

Britain on Tuesday sanctioned Maritime Mutual, the New Zealand-based marine insurer that was the subject of a Reuters special report into how it had helped in the trade of tens of billions of dollars of Iranian and Russian oil.

A dark fleet of tankers carried tens of billions of dollars of Iranian and Russian oil to Asia, evading Western sanctions. Reuters found the ships were connected by one thing: a small insurance company in New Zealand, run by a British family.