UPDATE 1-EU holds out for more after AstraZeneca offered 8 mln extra COVID-19 shots

* Astra had committed to at least 80 mln shots in Q1

* EU funded two UK plants under deal with Astra - sources

* Astra says UK has priority for doses produced there
(Adds detail, background)

By Francesco Guarascio and Sabine Siebold

BRUSSELS, Jan 29 (Reuters) - AstraZeneca offered
eight million more doses of its COVID-19 vaccine to the European
Union to try to defuse a row over supplies, but the bloc said
that was too far short of what was originally promised, an EU
official told Reuters.

The Anglo-Swedish firm unexpectedly announced cuts in
supplies to the EU last week, citing production problems at a
Belgian factory, triggering a furious response from the bloc.

EU officials said that meant a 60% cut to 31 million doses
in the period to the end of March, a major blow for its
27-member countries which are already lagging vaccination
campaigns in Israel, Britain and the United States.

The EU official directly involved in the talks said
AstraZeneca offered earlier this week to increase deliveries to
possibly 39 million doses in the first quarter, but that was
deemed inadequate. The size of the AstraZeneca's offer has not
previously been reported.

Under a contract agreed in August, the company should have
supplied at least 80 million doses to the EU in that period, the
official said, and possibly even 120 million "depending on how
you read the contract".

A second EU official said in a media briefing on Wednesday
that the company had proposed to supply a quarter of the agreed
volume of doses through March, which in the contract amounted to
a "three-digit" figure - consistent with nearly 40 million out
of a total of 120 million mentioned by the first source.

AstraZeneca's chief executive Pascal Soriot told newspapers
on Tuesday the company had no legal requirement to deliver to
the EU on a precise timetable, because it had only committed to
supplying vaccines under a "best-effort" clause.

At a meeting with EU officials on Wednesday, Soriot repeated
this and made no new offer of extra doses from the 39 millions
pledged earlier in the week, the first EU official said.

NO UK DOSES

To make up for the shortfall caused by problems at a factory
in Belgium, EU officials asked AstraZeneca to re-route to the
bloc some of the doses it manufactures in Britain.

But Soriot said at Wednesday's meeting that AstraZeneca had
contractual arrangements with Britain that prevented the company
from diverting doses produced there to the EU, two EU officials
said.

AstraZeneca did not respond to repeated requests for
comment.

On Friday, European Commission head Ursula von der Leyen
reiterated that AstraZeneca had binding obligations and could
not to make commitments with other buyers that would trump the
EU's deal.

Britain has a contract with AstraZeneca for 100 million
doses that was signed before the EU deal for at least 300
million shots.

Two officials said the EU's contract committed it to paying
336 million euros ($406 million) to AstraZeneca, mostly to
finance production of vaccines at four named factories. Two of
these, run by Oxford Biomedica and Cobra Biologics, are in
Britain, while the others are in Germany and Belgium.

"Part of the money went to the UK," one of the officials
said.

Asked about the EU requests, Britain said the EU had
established its own supply chains, and declined to comment on
its own or the EU's contracts with AstraZeneca.

The European Commission declined to comment.

The EU has not yet approved the AstraZeneca vaccine, which
is already being used in Britain. A decision is scheduled later
on Friday.

($1 = 0.8261 euros)
(Reporting by Francesco Guarascio @fraguarascio; Additional
reporting by Sabine Siebold, Paul Sandle and Ludwig Burger.
Editing by Catherine Evans and Mark Potter)