
A PSNI spokesman said: 'Police are advising of delays leaving Belfast country-bound on the Sydenham by-pass due to slow moving traffic.
'Road users are advised to avoid if possible and to leave extra time for their journey'.
A slow-moving convoy of tractors has caused traffic disruption in Belfast as several fuel protests are expected to be held in Northern Ireland.
Northern Ireland Health Minister Mike Nesbitt has asked protesters not to block roads, warning that the lives of those seeking medical treatment could be put at risk.
Traffic clogged up on the Sydenham bypass near Belfast City Airport around noon, hours after passengers were warned there may be traffic disruption and to leave more time for travel.
Tractors travelled down the bypass in the direction of Bangor towards City Airport, with some cars undercutting them on the cycle route to get past on the inside.
A PSNI spokesperson said: "Police are advising of delays leaving Belfast country-bound on the Sydenham by-pass due to slow moving traffic.
"Road users are advised to avoid if possible and to leave extra time for their journey."
Mr Nesbitt said he would be concerned if roads were blocked.
He said: "Just engage in legitimate legal protest.
"Today, as is the case every day, there will be well over 100,000 engagements or interactions between the HSC and the public.
"Thousands and thousands of them depend on the workforce getting from A to B, or for patients or service users getting from B to A in a timely manner.
"Ultimately, the logic to that is disruption threatens life.
"My plea is let the health and social care system work as it is supposed to work."
Ulster Unionist leader Jon Burrows said there should be an emergency meeting of the Stormont powersharing Executive to discuss rising fuel prices.
He said: "When people block roads for whatever purpose, it has a lot of unintended consequences.
"Right now there will be emergency services who will struggle to get to calls, there will be key workers who will not be able to get to work."
Mr Burrows added: "I understand the concern about the cost of fuel, about the cost of living crisis, but we need to have calm leadership and cool heads.
"I would ask the people involved in blocking roads to stop.
"This Executive needs to stand up and deliver in terms of convening an emergency meeting to decide what we are going to do about the cost-of-living crisis."
The Belfast disruption comes after similar demonstrations south of the border disrupted fuel supplies, port operations and traffic in city centres and on motorways for a week.
Although blockades at Ireland's only oil refinery and elsewhere were cleared at the weekend, smaller protests continued on motorways around Dublin on Monday - and a protest is due to be held at Leinster House on Tuesday, to coincide with a confidence vote in the government.
First Minister Michelle O'Neill and deputy First Minister Emma Little-Pengelly last week wrote to Prime Minister Sir Keir Starmer urging him to bring forward a package of support measures for people in the region.
They asked Westminster to look at reducing fuel duty, targeted support for hauliers, farmers and small and medium enterprises, and a comprehensive cost-of-living support package.
The cost of petrol, diesel and marked gas oil ("green diesel") has soared since the war in Iran.
The US and Israel began bombing Iran on February 28, after which the Iranians began an effective blockade of vital trading route the Strait of Hormuz, disrupting energy and fuel supplies.
Protests were expected to take place across Northern Ireland today at 2pm over fuel costs.
They will reportedly take place on Westlink, Belfast, M1 at Sprucefield, Nutts Corner, Sandyknowes Roundabout, Larne Harbour, Ballygawley Roundabout, Toome and Omagh town centre.
But it is unclear who is organising the protests - the Ulster Farmers' Union has said it has had "no involvement" in the organisation of 'planned fuel protests' and its chair has called on members not to take part on Tuesday.
And the PSNI have said they are aware of the reports of the protests and are monitoring the situation.
Earlier Agriculture Minister Andrew Muir urged potential protestors to "think twice" about their actions, with demonstrations anticipated in up to eight locations.
Mr Muir added: "Your actions will actually disadvantage those you proport to stand for in terms of the farming community.
"They will then have real challenges in terms of brining livestock to mart and slaughter and in relation to milk tankers.
"We had issues last week in the Republic where people were struggling to get to cancer appointments, to be able to care for loved ones.
"That is not a situation we want to see."
Meanwhile East Londonderry MLA Claire Sugden called for more support for farmers and households with fuel costs, saying the burden is "not optional".
"People were already dealing with a high cost of living, and this sudden increase in fuel prices has made things even more difficult," the former Justice Minister said.
"For many households, it is not about cutting back anymore, it is about whether they can afford to heat their home or get through the week."
A post from NI Direct added: 'Protests are planned at a number of locations in Northern Ireland over the next few days.
'You should allow extra time for journeys due to potential traffic disruption.
'Information on any traffic issues will be available on the website: https://trafficwatchni.com/twni/