Relatives of men who died when a Peterhead fishing boat sank have threatened to petition the prime minister to stop a wreck survey.
The Trident sank in 1974 off Caithness with the loss of seven lives.
Some relatives say they are angry over not being consulted about government plans to survey the wreck as they believe it would be disturbed.
Jeannie Ritchie, who lost her father and husband, said: "We are proposing to go to 10 Downing Street."
The Trident disappeared in October 1974 while in transit from the west coast of Scotland to her home port of Peterhead. The wreck was discovered by amateur divers in 2001.
The Advocate General for Scotland has responsibility for obtaining all relevant or potentially relevant evidence in relation to the causes of the loss.
It has been ruled that a detailed underwater seabed survey of the wreck should take place to collect this evidence, which will include video images and measurements which could help to establish the probable cause.
The survey, which will take place in June, will be funded by the Department for Transport.
Aberdeen firm Subsea 7 has been chosen as the main contractor for the survey.
Mrs Ritchie said: "We are proposing to go to 10 Downing Street with a petition to Tony Blair asking him to stop this survey and to question why himself and Government departments are not responding to our plea.
"We are being totally ignored.
"We do not know how the department's going to do it but no way can they cut into that vessel.
"What's going to happen to the remains of seven men that are lying resting in the Trident?"