CYCLISTS have slammed protective barriers on key London bridges, moaning they take up too much room.

The concrete blocks, installed on Sunday night, are designed to prevent vehicles mounting the pavement and hitting pedestrians.

The barricades were installed on Waterloo, Lambeth and Westminster bridges overnight in the wake of the atrocity which left seven dead and 48 injured.

16 Concrete barriers were installed on Westminster Bridge last night - almost two months after a terror attack there Credit: News Group Newspapers Ltd

16 Concrete blocks could be seen placed at the ends of the bridge this morning Credit: Reuters

16 Mounted police were seen crossing Westminster Bridge today close to the new security barricades Credit: AP:Associated Press

16 The concrete blocks bookend Westminster Bridge, which was the scene of a horrific attack in March Credit: Reuters

16 Mounted police ride past a security barrier on Waterloo Bridge today Credit: Getty Images

But bike campaigners reckon they are dangerous because cycle lanes have been narrowed to make room for the structures.

Sam Jones, the Campaigns Co-ordinator at Cycling UK, said: "Given the number, scale and type of attacks in the last nine weeks, it is understandable and right that the police and Transport for London are putting in measures to protect key points of infrastructure and the public from likely threats.

"Having been contacted by Cycling UK members about what this means for the current cycling infrastructure, there is clear concern what this might mean for protecting our most vulnerable road users on their daily and regular journeys as well.

"We are speaking with the London Cycling Campaign, and together we will look to contact TfL and the Met to work with them to ensure that high standards of cycle provision can be maintained while also preserving the necessary security measures."

It comes after authorities ruled out measures to install barriers on London Bridge just 24 hours before three terrorists went on a rampage and drove a van at crowds of people.

The City of London Corporation said there were "no current plans" to install bollards on the historic structure on Friday.

While barriers haven't been installed on London Bridge, it was reopened this morning as defiant Londoners returned to work.

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Anti-terror barricades were installed at Buckingham Palace and Windsor Castle in the wake of the Westminster terror attack, but not on the bridge itself.

However concrete bollards were erected last night following the attack in March when jihadist Khalid Masood mowed down and killed four pedestrians on the pavement before fatally stabbing police officer Keith Palmer.

16 Security blocks were erected on Westminster Bridge overnight, in response to Saturday's attack Credit: Getty Images

16 As people returned to work this morning, they noted the new installation designed to keep Londoners safe Credit: Getty Images

16 A man walks through the gap in the concrete blocks which have been erected at the end of Westminster Bridge Credit: Reuters

16 Bold Londoners have been out and about in the city today where new security barriers have been installed on bridges Credit: PA:Press Association

The structures, made of concrete and metal, appeared on the bridges overnight with people sharing images on social media.

Some questioned whether the barricades would leave enough space for cyclists.

Clint Seidel tweeted: "Barriers on Waterloo Bridge. Hope space is made safe for cyclists".

Met Police Commissioner Cressida Dick said the barriers will help stop the kind of terror attacks seen in the city in recent months.

She told LBC: "This morning you will see some hostile vehicle blocking on some of our bridges.

16 New metal security barriers have also been placed on Waterloo Bridge, which is close to the scene of two other terror attacks on London Credit: Getty Images

16 A young woman makes her way past the concrete blocks, which are now visible on three bridges in London including Westminster Credit: Reuters

16 There were calls for barriers to be installed on Westminster Bridge in the wake of the atrocity in March Credit: PA:Press Association

16 People have questioned whether the barriers will leave enough room for cyclists on the road Credit: Reuters

16 The barriers are designed to protect the public crossing some of the major bridges in the city Credit: Reuters

"That's in response to Saturday night's attack which involved a bridge and pedestrians being hit with a vehicle, as it was in Westminster.

"We will have more armed policing on and near the bridges and people should be prepared for that."

Prime Minister Theresa May today said the UK's threat level will remain at "severe" following the attack on London Bridge less than 48 hours ago.

She also said police have identified all three of the attackers.

Armed cops have been carrying out raids across London in the wake of the atrocity.

16 Londoners were advised they can expect to see the barriers across bridges in London in the wake of the attack Credit: Getty Images

16 Met Police Commissioner Cressida Dick said the barriers will help stop the kind of terror attacks seen at Westminster and London Bridge Credit: News Group Newspapers Ltd

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