Arlene Foster chatting to Robin Newton and William Irwin at the event. Photo Colm Lenaghan/Pacemaker Press

The hugely unusual situation arose at the Stormont Hotel in east Belfast where the DUP leader was launching the platform on which her party is fighting the election campaign.

At such events, all parties invite journalists to attend so that they can see the document and then question the party about what it is proposing.

As Mrs Foster began her 20-minute speech, she told those present – who included many, but not all, of the DUP’s 38 candidates – that she had been “struck down with the cold, slash ‘man-flu’, so I hope my voice holds up for the presentation this morning.”

Sign up to our daily newsletter The i newsletter cut through the noise Sign up Thanks for signing up! Sorry, there seem to be some issues. Please try again later. Submitting...

It was audible from Mrs Foster’s voice that she had a sore throat.

However, at the conclusion of the DUP leader’s speech, Mrs Foster then left the podium.

Deputy leader Nigel Dodds stepped up and thanked Mrs Foster for “setting out the list of positive achievements” and a “positive vision for 2017 and moving forward”.

He described the manifesto as “a solid platform, a positive vision for Northern Ireland moving forward” – but then made clear that no one could ask questions, saying of Mrs Foster “she has a bad cold and flu”.

Mr Dodds thanked “the members of the press and media for coming along to cover the launch of our manifesto and the policies and principles set out there ... so we look forward to the verdict of the electorate ... thank you again for coming this morning.”

BBC Northern Ireland’s veteran political correspondent Gareth Gordon said he had “personally never experienced such a thing”.

One senior DUP aide suggested that the decision was due to Mrs Foster not feeling well.

However, no one else from the party took questions either.

By contrast, a week earlier UUP leader Mike Nesbitt took numerous questions from journalists at the UUP manifesto launch – even though most of them were difficult and focused on the internal UUP unhappiness over his comment about voting for the SDLP.