Last checked at 
* EU triggers Brexit clauses
* EU tries to restrict vaccine exports to UK
* UK seeks urgent answers, expresses concern
* Irish PM expresses concerns to EU chief
(Adds latest comment from Johnson, report that EU has U-turned)
By Andy Bruce, Kate Holton and Marine Strauss
LONDON/BRUSSELS, Jan 29 (Reuters) - The European Union on
Friday sought to restrict exports of COVID-19 vaccines through
the Irish border to the United Kingdom by invoking emergency
clauses in the Brexit divorce deal, sending shockwaves through
both Ireland and Northern Ireland.
In a steep escalation of the EU's fight to secure vaccine
supplies, the EU triggered clauses in the Northern Irish
Protocol that would limit the supply of vaccines crossing the
Irish border into the United Kingdom.
Northern Irish unionists cast the move as an act of
hostility while Irish Prime Minister Micheál Martin sought
urgent clarification from European Commission President Ursula
von der Leyen.
As Britain considered its response, British Prime Minister
Boris Johnson said the EU had to clarify its intentions to
ensure it honoured its commitments to Northern Ireland.
"He expressed his grave concerns about the potential impact
which the steps the EU has taken today on vaccine exports could
have," Johnson's office said in a readout of a phone call
between Johnson and von der Leyen.
It was not immediately clear if the move to invoke the
article, set out in a document published on Friday, would come
into effect immediately - or indeed if it was some sort of
mistake.
A link to the document was no longer working at 2050 GMT.
A Sky News reporter said the EU had withdrawn its move to
override the Northern Irish treaty. Euronews said the whole
thing was a 'mistake' and an 'oversight'.
The Commission did not comment when contacted by Reuters for
clarification but was expected to make a statement shortly.
The swiftest mass vaccination drive in history is stoking
tensions across the world as big powers buy up doses in bulk and
poorer nations try to navigate a financial and diplomatic
minefield to collect whatever supplies are left.
IRISH BORDER
Preserving the delicate peace in Northern Ireland without
allowing the United Kingdom a back door into the EU's markets
through the UK-Irish 310-mile land border was one of the most
difficult issues of the Brexit divorce talks.
The EU's action - even if it rescinds the decision -
triggered anger.
Northern Ireland First Minister Arlene Foster described as
"an incredible act of hostility" the decision by the EU to
invoke Article 16 of the Northern Irish Protocol, which allows
Britain or the EU to take unilateral action if there is an
unexpected negative effect arising from the agreement.
"The European Union has once again shown it is prepared to
use Northern Ireland when it suits their interests but in the
most despicable manner – over the provision of a vaccine which
is designed to save lives," Foster said.
The EU move is designed to prevent the open border between
EU-member Ireland and Northern Ireland from acting as a backdoor
for vaccine supplies into the United Kingdom.
Article 16 was devised as a last resort to alleviate serious
disruption to trade in Northern Ireland after Brexit.
The EU, whose member states are far behind Israel, Britain
and the United States in rolling out vaccines, is scrambling to
get supplies just as the West's biggest drugmakers slow
deliveries to the bloc due to production problems.
The British-Swedish drugmaker AstraZeneca has been
caught in the crosshairs after it said last week it would fall
short of delivering promised vaccines to the EU by March because
of production problems in Belgium.
That has angered Brussels which has demanded to know why it
cannot divert supplies from its British sites which have been
producing millions of shots for British citizens.
The European Commission has agreed a plan to control exports
of vaccines from the bloc, including to Britain, arguing it
needed to do so to ensure its own supplies.
The Commission said its move to invoke Article 16 was
justified to "avert serious societal difficulties" in EU states
due to a lack of vaccine supply, the document published on
Friday said.
Britain has its own domestic supply chain in place for
AstraZeneca's shot, including rolling it out in Northern
Ireland, but it imports Pfizer's vaccine from a factory in
Belgium.
Britain had threatened to trigger the Article 16 safeguard
measures earlier in the month if there were "serious problems"
in supplying supermarkets in Northern Ireland.
(Reporting by Kate Holton, Andy Bruce and William James;
Editing by Guy Faulconbridge and Daniel Wallis)
