The existing footbridge to Lossiemouth’s East Beach has been permanently closed with the removal of a walkway section.
The crossing, which is due to be replaced over the next 18 months, was declared dangerously unsafe by engineers last July.
Barriers preventing public access to the bridge have been repeatedly vandalised and, with warmer weather attracting people to the beach, there are fears that more pedestrians will attempt to use the crossing.
Moray Council, which has a duty of public safety and protection from infrastructure, will remove one of the centre spans to prevent any further use.
Spans in the centre over the River Lossie are the highest parts of the bridge and the weakest section of the structure.
The operation will be carried out by Moray Council staff over the next weeks.
The process to design and build a replacement bridge, funded by the Scottish Government, has commenced but is at an early stage.
Moray Council leader Graham Leadbitter said: “There is great concern that further and rapid deterioration will occur, particularly the centre spans, with weather and pedestrian use.
“If these centre spans collapse into the river below we could be dealing with a tragedy, which can be avoided by taking this action.
“I’m sure the people of Lossiemouth will agree with this action, taken as it is with the best interests of public safety at heart.”
He added: “The Scottish Government have pledged to fund a replacement, and we are well underway with the necessary steps to make that happen.
“Meantime our paramount duty here is one of public protection.”