UPDATE 1-UK supermarkets want 'urgent intervention' to ensure supplies to Northern Ireland

* Three month grace period to adapt systems ends March 31

* UK supermarkets say current proposals "unworkable"

* UK supermarkets say long term solution needed before March
31

* Says disruption inevitable if solution not found
(Adds detail, government response)

By James Davey

LONDON, Jan 13 (Reuters) - Britain's major supermarkets have
warned the government that "urgent intervention" is needed to
prevent significant disruption to Northern Ireland food supplies
in the coming months.

Britain is no longer part of the European Union's single
market and customs union, but Northern Ireland has a foot in
both camps – part of the UK's customs territory but also still
aligned with the EU's single market for goods.

Britain and the EU agreed in December that supermarkets
selling into Northern Ireland would have a three-month grace
period to adapt their supply systems to the post-Brexit trading
reality.

Despite that some supermarkets in Northern Ireland have had
shortages of fresh goods usually imported from Britain since the
turn of the year because they have struggled to shift to new
processes and bureaucratic procedures.

The bosses of retailers, including Tesco,
Sainsbury's, Asda and Marks & Spencer,
have written to Cabinet Office minister Michael Gove, warning
the situation could worsen.

In the letter, seen by Reuters, they said it was essential a
long-term solution is agreed with the EU before the current
grace period for simplified controls ends on March 31.

"All our businesses and suppliers have invested
significantly in the last few months to avoid disruption but
that will become inevitable if the proposals governing movement
of food from Great Britain to Northern Ireland are adopted," it
said.

"We recognise the European Commission needs to see increased
compliance to support the concessions it granted through the
Northern Ireland protocol but the current proposals, increased
bureaucracy and certification in such a short timescale, are
unworkable."

The CEOs called on Gove to create a dedicated working group
to co-ordinate government agencies to integrate customs and food
controls, and to use the supermarket groups' experts to develop
the best solution.

And they want the government to agree with the EU that more
time is required to implement a new system.

"It also requires an open discussion with the EU explaining
why we can't accommodate changes to the current approach to
transporting food to Northern Ireland but stressing we are
working towards a robust system as quickly as possible," the
letter said.

A British government spokeswoman said a new dedicated team
had already been set up and would be working with supermarkets,
the food industry and the Northern Ireland Executive to develop
ways to streamline the movement of goods in accordance with the
Protocol.

“The grace period for supermarkets and their suppliers is
working well, goods continue to flow effectively between Great
Britain and Northern Ireland and we are working intensively with
industry as new requirements come in," she said.
(Reporting by James Davey; additional reporting by Liz Piper,
Editing by Nick Macfie and Jane Merriman)