Climate activists on board the Rainbow Warrior are to sail into the heart of Glasgow after officials agreed to allow the ship into the Cop26 restricted zone.

Port authorities wanted to block the famous vessel from entering the area, which bans craft from the stretch of the Clyde next to the SEC conference centre, but on Monday afternoon Police Scotland confirmed the vessel was to be allowed to continue to its destination.

Activists Jakapita Faith Kandanga, 24, Edwin Namakanga, 27, Maria Reyes, 19, and Farzana Faruk Jhumu, 22, who are from communities which would be most affected by a changing climate, are on board the ship.

In a joint statement they said the “authorities understand that our presence at the climate summit is too important to shut out”.

“It’s ridiculous to think that climate talks could be held without the most affected people there and it’s positive that the police and port authorities have changed their minds,” they said.

“World leaders attending the talks could learn a lot from this co-operation. We have been ignored long enough, and now, with a safe passage to Glasgow, our voices must be heard at Cop26.”

Greenpeace said it had been warned by HMS Vigilant, as it approached the Firth of Clyde, that if the Rainbow Warrior continued its voyage it would be in breach of maritime laws and Police Scotland would “act appropriately”.

But the pressure group said that, following a meeting with Hettie Geenen, the ship’s captain, port authorities told her they would help facilitate the four youth climate activists’ arrival.

The four campaigners, from Namibia, Uganda, Mexico and Bangladesh, are just a handful of the thousands of protesters who are descending on the city as world leaders discuss how to fight a changing climate.

Police Scotland Assistant Chief Constable Gary Ritchie said: “Harbour authorities had been in regular communication with the Rainbow Warrior and had instructed that, due to the restrictions and some significant safety concerns, it could not sail to its intended destination.

“Despite this, the Captain of the Rainbow Warrior signalled her intent to continue.

“Accordingly, following consultation between police and harbour authorities, it was considered that the safest option for the crew of the Rainbow Warrior and wider public was to ensure the safe passage of the vessel to its destination.

“We are now engaging with Greenpeace and all relevant partners to ensure the safe passage of this vessel, it’s passengers and the wider public.”

Over the next two weeks of the conference, 120 dignitaries and heads of state are set to attend the UN event which has been billed as vital in stopping climate change and rising global temperatures.

As world leaders made their way to the city on Monday, Oxfam’s “big heads”, featuring Joe Biden, Boris Johnson, Emmanuel Macron, Angela Merkel, Justin Trudeau, Mario Draghi, Narendra Modi, Vladimir Putin and Xi Jinping, made an appearance along with a traditional Scottish pipe band in Glasgow’s Royal Exchange Square, where they were “blowing hot air”.

Nafkote Dabi, Oxfam’s climate change policy lead, said rich nations are not cutting emissions fast enough to keep the most vulnerable countries safe.

“We must all halve global emissions in the next nine years but we are heading in the opposite direction. Leaders must not delay a moment longer – every fraction of a degree costs lives,” she warned.

“Developed nations must live up to their promise from 12 years ago to deliver 100 billion dollars (£73 billion) every year to help vulnerable nations adapt to climate change and reduce emissions.

“This support should be in the form of grants – not loans – and half of it should be for adaptation. It is also critical that they agree a way to finance loss and damage for the unavoidable impacts of climate change that are already destroying homes and lives.”

Greta Thunberg, who inspired the climate strike movement across the globe, was surrounded by police officers and activists as she arrived at Glasgow Central railway station on Sunday night.

The 18-year-old is expected to take part in demonstrations during the summit, including a march through the city on Friday, organised by campaigning organisation Fridays for Future Scotland.

The demonstration will walk from Kelvingrove Park to George Square.

Ms Thunberg is also expected to speak at a rally taking place on Saturday, hosted by the Cop26 Coalition, which will march from Kelvingrove Park to Glasgow Green.

On Sunday, Extinction Rebellion marched through Edinburgh in solidarity with protests taking place across the world.