Cairnryan port blockade warning over P&O Ferries sackings.<br /><br />Unions have warned they could try to blockade the P&O Ferries terminal at Cairnryan if sailings resume.<br /><br />About 190 people joined a protest at the site over the company's decision to sack 800 workers last week.<br /><br />P&O has said the staff affected will be offered £36.5m and has denied breaking the law with the sackings.<br /><br />However, Prime Minister Boris Johnson said it appeared they had and could face fines running to millions of pounds.<br /><br />Since P&O announced the move it has faced heavy criticism from unions and from across the political spectrum.<br /><br />The protest at Cairnryan - where services to and from Larne remain suspended - was staged at about noon on Wednesday.<br /><br />It was organised by the RMT union - but they were joined by members of other unions and politicians.<br /><br />The RMT said it still hoped P&O might revoke the redundancies.<br /><br />If it does not - and sailings start again using agency workers - the union said it could attempt to mount what it described as a blockade and persuade customers to boycott the company.<br />P&O Ferries has argued that financial losses meant it would "not be a viable business" without making the changes.<br /><br />Chief executive Peter Hebblethwaite has apologised for the mass sacking.<br /><br />He said the decision had been "incredibly difficult" but was "the only way to save the business".