(Adds Telegraph report on N. Irish grace period)

By Guy Faulconbridge and Elizabeth Piper

LONDON, Feb 8 (Reuters) - Britain called on Monday for areset in relations with the European Union and a refinement of aBrexit deal covering trade with Northern Ireland, saying trustwas eroded when Brussels attempted to restrict COVID-19 vaccinesupplies.

Relations between Brussels and London strained by years ofbruising Brexit talks took a turn for the worse last month whenthe EU threatened to use emergency measures to stop coronavirusvaccines going from the bloc into Northern Ireland.

To avoid creating a hard border on the island of Ireland,Northern Ireland remained within the EU's single market forgoods under the Brexit deal, effectively creating a frontierwithin the United Kingdom.

The EU swiftly changed its position on the vaccines butLondon hopes to capitalise on the gaffe to win changes to theBrexit deal because the new rules have caused disruption inBritain's trade with Northern Ireland.

"It was a moment when trust was eroded, when damage was doneand where movement is required in order to ensure that we havean appropriate reset," Michael Gove, who is in charge ofimplementing the divorce deal, told a parliamentary committee.

Striking at the heart of the EU's project, Gove scolded thebloc for putting its members above the people of NorthernIreland by raising the prospect of checks on vaccines at theborder - something Brussels has long said it wanted to avoid.

"If people put a particular type of integrationist theologyahead of the interests of the people of Northern Ireland theyare not serving the cause of peace and progress in NorthernIreland, and that is my principal and overriding concern," hesaid.

"Pandora's Box has been opened and that is concerning ...who knows what Trojan horses will come out," Gove said, quotingformer Labour Foreign Secretary Ernest Bevin's words about theidea of joining a forerunner of the EU.

GRACE PERIOD

The EU's swift U-turn has emboldened British ministers, andlast week Gove sent a letter to European Commission VicePresident Maros Sefcovic demanding some changes to the so-calledNorthern Ireland protocol of the Brexit deal.

He demanded grace periods for the transport of food fromBritain to Northern Ireland be extended from a few months to atlast two years.

"There are a number of issues ... where we believe that wedo need refinement of the way in which the protocol operates forit to be effective in the interests of the people of NorthernIreland," Gove told the lawmakers.

The EU is poised to reject Britain's calls for a two-yearextension of the grace periods for post-Brexit trade in NorthernIreland, the Telegraph reported https://bit.ly/3cR0QvZ late onMonday, citing British government sources.

The European Commission, the EU executive, is likely toagree to only a three- to six-month extension of thearrangements in place for traders moving goods between Britainand the province, the report added.

Some Northern Irish politicians have called for the protocolto be scrapped, saying it has caused shortages in supermarketsand impeded the delivery of other goods.

The European Commission declined to comment directly onGove's remarks, but a spokeswoman said last December's Brexitdeal would not be re-opened.

"Our focus remains on the implementation of the Protocol andthe decisions adopted by the Withdrawal Agreement JointCommittee at the end of last year," she said.

The EU and Britain have agreed to work intensively toresolve the difficulties and Gove is expected to meet Sefcovicon Thursday to try to find a way forward.

Politicians have been keen to avoid a hard border betweenNorthern Ireland and Ireland, fearing it could be detrimental tothe 1998 peace agreement that ended three decades of conflict inthe province.(Reporting by Guy Faulconbridge in London with additionalreporting by Robin Emmott in Brussels; Writing by ElizabethPiper; Editing by David Clarke, Janet Lawrence and AlexRichardson)