Nic Lonsdale, duty watch manager at Portland Coastguard, said: "We are urging people to observe the warning signs and stay away from the edge." The cliffs at Durdle Door and Lulworth have been crumbling since the start of year.
In January, the steps to the famous landmark collapsed. Earlier this month, coastguards warned that the path was beginning to fall away.
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Friday's weather for the west of the region
Friday's weather for the east of the region
The Bishop of Salisbury has called the attack on Segei Skripal and his daughter Yulia "a violation of our community."