Two attempts to blow up a World War II parachute mine off the Margate coast have failed.
Dover Coastguard said another attempt to detonate the device would be carried out on Saturday.
In the meantime, the bomb has been marked in the water and ships have been warned to stay clear, a spokesman said.
The unexploded device was brought up by a fishing boat in the Thames Estuary, which caught it in one of its nets and raised the alert.
Earlier, coastguard spokesman Phil Binks said the parachute mine was believed to be a 1,000lb bomb.
The Margate lifeboat and Royal Navy bomb disposal experts were moving it to waters off the east Kent resort where it would be detonated, he added.
Mr Binks said the fishing vessel had found a similar device in the past.
The Germans used parachute mines against British targets in 1940 and 1941.