Paul Golding, the leader of the fringe far-right group Britain First, has been charged with an offence under the Terrorism Act after refusing to give police access to his phone.

He was stopped at Heathrow airport in October while returning from a trip to the Russian parliament in Moscow by officers from the Metropolitan police’s counter-terrorism command.

He refused to give the Pin codes for a number of his electronic devices. Golding, 38, is charged with refusing to comply with a duty under Schedule 7 of the Terrorism Act.

A Met spokesman said Golding, of Bexley in south-east London, was charged by postal requisition on Wednesday. He is due to appear at Westminster Magistrates’ Court on 27 February.

In a statement Golding said he was not a terrorist and described the charges as “an abuse of legislation”. Schedule 7 allows police to interrogate, search and detain anyone for up to six hours at UK ports.

It is designed to determine whether an individual is involved in the “commission, preparation or instigation” of acts of terrorism.

Britain First achieved brief notoriety in late 2017 after Donald Trump retweeted anti-Muslim messages sent by the party’s then deputy leader, Jayda Fransen, prompting international condemnation.

The group was fined more than £44,000 last July for what the Electoral Commission said were multiple breaches of electoral law, including undeclared donations and a failure to provide proper accounts.