David Cameron has warned voters in Northern Ireland of the potential economic impact of Brexit as he continues a tour of the UK setting out the case for staying in the European Union (EU).
The Prime Minister said the country's economy and farming industry were too closely linked to the EU to risk the "leap in the dark" of voting to quit the 28-nation bloc.
Northern Ireland's political parties are split on the issue, with the Democratic Unionists backing "leave" and Sinn Fein, the SDLP and the cross-community Alliance Party in favour of "remain".
A declaration is expected next week from the Ulster Unionists.
Northern Ireland Secretary Theresa Villiers is one of five cabinet ministers who have broken ranks to campaign for the UK to end ties with Brussels.
Speaking to locals at Ballybollen House farm in County Antrim during his visit, Mr Cameron stressed the importance of EU membership to the industry.
"Many of those who want to ask you to vote to leave are actually not really sure whether they want to leave or not," he said.
"I think that should set alarm bells going in the minds of voters about the potential dangers and risks that we face if we leave."
Treasury figures put the number of jobs in Northern Ireland linked to EU trade at 50,000, with exports up over 50% in real terms since 1998.
Before speaking at the farm, Mr Cameron toured the Bushmills distillery in Co Antrim, where he was shown how barrels are sealed.
A spokeswoman for Old Bushmills Distillery said the firm was "delighted" to have hosted a visit by Mr Cameron.
"Old Bushmills Distillery is part of a global company, selling in global markets," she added.
"We believe the matter of UK membership of the EU is for individual voters to decide on. Access to the EU market of 500 million people is important in a global context and will remain so."