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.
More top news
Hampshire police arrest seven more men in investigation into an alleged conspiracy to commit serious sexual offences on the Isle of Wight.
The Government scheme would benefit those aged under 40 but will only run for five years.
Becoming windy with cloud and showers this afternoon. Heavy rain on the way later