Before he became prime minister, Boris Johnson had promised businesses in Northern Ireland they would face "no forms, no checks, no barriers."
Journalist Lyra McKee, 29, was shot dead while observing rioting in the Creggan estate, Londonderry on April 18, 2019.
Police said the charge was "significant" in the investigation into the killing of Lyra McKee but that "the quest for the evidence ... remains ongoing."
Irish politicians agreed to a power-sharing deal after three years of deadlock.
Tactics, votes and alliances - the Northern Irish case throws up a host of issues.
McDonald's has apologised for a Halloween marketing campaign in Portugal that referenced one of the darkest days of the Northern Ireland sectarian conflict.
The British province lifted restrictions on abortion and a ban on same sex marriage on Monday at midnight.