British Prime Minister Boris Johnson will hold brief face-to-face talks with French President Emmanuel Macron at the G20, Downing Street said Friday, with the two nations locked in a fishing rights dispute.

The leaders will meet at the summit starting in Rome on Saturday as an escalating row over rights for French fishing boats has seen Britain summon the French ambassador.

Johnson and Macron will hold a brief "brush-by" meeting on the sidelines of the summit to "discuss a range of issues", a spokesman for the British prime minister told journalists, without confirming the time and date.

The two sides are at loggerheads over licensing rules for EU boats wanting to operate in waters around Britain and the Channel Islands.

France has been incensed by the rejection of some of its vessels by Britain and the self-governing islands of Jersey and Guernsey, which depend on London for defence and foreign affairs.

France has warned that continued denial of licences would lead to retaliatory measures as soon as next week, including time-consuming checks on all products and a ban on UK vessels landing seafood.

London has promised "an appropriate and calibrated response" to the French measures, since the British fishing industry depends on French ports as a gateway to Europe, its main export market.

Britain's Foreign Secretary Liz Truss has summoned the French Ambassador to London, Catherine Colonna, to a meeting Friday afternoon to explain France's "threats".