Two Just Stop Oil protesters jailed after scaling a bridge at the Dartford Crossing have lost a bid to challenge their sentences at the Supreme Court.

Morgan Trowland, 40, and Marcus Decker, 34, were jailed after using ropes and other climbing gear to scale the Queen Elizabeth II Bridge, causing gridlock when police closed it to traffic last October.

In July, the protesters lost an appeal over what their lawyers said were the “extraordinary length” of Trowland’s three-year sentence and Decker’s jail term of two years and seven months.

Court of Appeal staff confirmed on Wednesday that judges have refused to grant permission for the two men to take their case to the UK’s highest court.

Lady Chief Justice Lady Carr, Mrs Justice Thornton and Mrs Justice Cutts rejected the further appeal bid at a hearing in London.

In their July ruling, the judges acknowledged the “long and honourable tradition of civil disobedience on conscientious grounds” and that the sentences handed to Trowland and Decker went “well beyond previous sentences imposed for this type of offending”.

But Lady Carr said the jail terms were “not excessive” and reflected “Parliament’s will” under new laws enacted under the Police, Crime, Sentencing and Courts Act last year which introduced a new “fault-based public nuisance offence for what obviously will include non-violent protest behaviour, with a maximum sentence of 10 years’ imprisonment”.

She said the sentences met the “legitimate” aim of deterring others from such offending.

The judge added: “The sentences should not be seen as having a ‘chilling effect’ on the right to peaceful protest or to assembly more generally – deterrence and ‘chilling effect’ are not the same.

Daniel Friedman KC, representing the activists, had previously argued their jail terms were “the longest ever handed down in a case of non-violent protest in this country in modern times”.

The two men’s trial at Basildon Crown Court was told the bridge was shut from 4am on October 17 until 9pm the next day, sparking traffic jams as motorists were forced to use tunnels instead.

Structural engineer Trowland, of Islington, north London, and private tutor Decker, of no fixed address, denied causing a public nuisance, arguing it was a protest.

Their trial was told the protesters ascended to a point close to 200ft above the road and unfurled a “giant Just Stop Oil banner” and “rigged up hammocks and stayed there”.

The men came down at about 5.30pm on October 18 “with the help of police and a very tall cherry picker crane”, but the bridge, which links the M25 in Essex and Kent, was not reopened to traffic until later.

Essex Police said those affected by the disruption included a “heavily pregnant woman who needed urgent medical help”.

Another person missed the funeral of their best friend of 35 years, the force said, and a business lost more than £160,000 in earnings.

In April, a jury unanimously found Trowland and Decker guilty of causing a public nuisance.

Just Stop Oil previously said sentencing Judge Shane Collery KC was “trying to set a precedent” and “deter people”.

The environmental campaign group said Decker, a German citizen who it said has leave to remain in the UK, faces deportation after serving his sentence.

Trowland has six previous convictions relating to protests, while Decker has one, with lawyers for the pair previously saying they would not take part in further disruptive protests.