Environmental activists have indicated they will continue blocking the M25 despite facing up to two years in prison.
Insulate Britain said in a statement that “right now our campaign goes on”.
It has shut down parts of the M25 five times in just over a week.
More than 200 people have been arrested, according to the Department for Transport (DfT).
But it has been reported that many people have returned to demonstrate on the motorway after being arrested and released during previous incidents.
Anyone who breaks the injunction could be found to be in contempt of court, which carries a maximum penalty of two years in prison or an unlimited fine.
Home Secretary Priti Patel said the “important injunction” means “people can get moving again” on the UK’s busiest motorway.
“We will not tolerate lives being put at risk,” she said.
“Those who continue to do so risk imprisonment.”
Transport Secretary Grant Shapps added: “Invading a motorway is reckless and puts lives at risk.”
Shortly after the injunction was implemented on Wednesday morning, Insulate Britain issued a statement which read: “We do not know the terms of the injunction and right now our campaign goes on.”
The group later said: “For 10 days now, campaigners from Insulate Britain have been blocking motorways to urge our Government to make a meaningful statement we can all trust on insulating and retrofitting the houses of this country.
“Doing anything less would be a betrayal of any UK government’s first duty: to protect the British people.
“We urge you to ensure this meaningful statement is made swiftly so ordinary people can stop blocking roads.”
Assistant Chief Constable Chris Noble the National Police Chiefs’ Council lead for policing protests, told BBC Radio 4’s Today programme that the police “aren’t anti-protest but we are pro-responsibility”.
He continued: “This is not a benign supermarket car park that this is taking place on.
“The people most likely to come to harm at the moment is probably initially police officers who are having to run across motorways to try and remove protesters as well as ironically keep them safe from themselves.”
The High Court order, which officially came into force on Wednesday morning, prohibits anyone from “blocking, endangering, slowing down, preventing, or obstructing the free flow of traffic onto or along or off the M25 for the purposes of protesting”.
The order also forbids causing damage to the motorway’s surface or any apparatus around it, “locking on” to any other person or object on the road, erecting a structure, tunnelling nearby, entering the motorway unless in a vehicle, abandoning any vehicle or item with the intention of causing an obstruction and refusing to leave the area when asked by police.
Mr Justice Lavender, who granted the injunction, said there will be a further hearing on October 5 at 10.30am.
The DfT said the Government could return to court to seek additional powers of arrest in relation to the protests.