The broadcasting watchdog Ofcom is investigating a complaint made against GB News’ Don’t Kill Cash campaign.
The campaign, which has more than 166,000 signatures, warns about Britain “becoming a cashless society”.
It also calls on the government to introduce legislation to protect the status of cash as legal tender.
Ofcom said its guidelines require broadcasters to not express views on “matters of political and industrial controversy or current public policy.”
“Our investigation does not seek to question the merits of the campaign itself,” the watchdog added in a statement.