The Duke of Cambridge is due to take part in an online ceremony to honour the emergency services.
The annual Emergency Services Festival of Thanksgiving – otherwise known as the 999 Festival – is going digital this year due to the coronavirus pandemic.
Held on the Friday closest to September 9, the multi-faith festival helps commemorate the thousands of emergency responders who have died in the line of duty.
This year, more than 300 NHS and other emergency workers have died after contracting Covid-19 on duty.
The 999 Festival had been scheduled to be hosted in Belfast Cathedral, but will instead be broadcast on Facebook, Twitter and LinkedIn at 2pm on Friday.
William, who was himself an air ambulance pilot, is due to say: “This year, more than ever, we have been repeatedly reminded of the sacrifices made by all those in the emergency responder community, as they worked tirelessly to protect us against Covid-19 and keep the country going in the most challenging circumstance.”
He will add: “They showcase the very best that our country has to offer, and this is never more apparent than at times like these.”
The festival will include music from the Blue Light Choir and videos from the chairs of the Police, Fire and Ambulance Councils and the director of Her Majesty’s Coastguard.
First Minister of Northern Ireland Arlene Foster, First Minister of Scotland Nicola Sturgeon and First Minister for Wales Mark Drakeford and Health Secretary Matt Hancock are also due to speak.
Tom Scholes-Fogg, founder and chief executive of the 999 Festival, will say: “Given events in our country and across the globe we simply could not let this year go by without honouring our 999 heroes.
He will add: “The emergency services is about partnership, and events such as the 999 Festival where the NHS and emergency services are together as equal partners is important.”
Those wishing to watch the festival can visit the festival’s website at 999festival.org.uk and click on the social media links in the right hand corner of the page.