Party officials intervened after police became concerned about the "noisy and inappropriate behaviour" of Sally Noel, 53, at a gathering for conference exhibitors on Wednesday evening at the Stakis Hotel, in Blackpool.
Special Branch detectives had been observing the behaviour of Mrs Noel, who has four children, since she arrived on Sunday night, and they asked her whether she intended to follow the Prime Minister "for the rest of her life".
Mrs Noel, who is not a member of the Labour Party, claims to be a member of a group of Lloyd's investors, or "names", and she is seeking compensation from the Government of more than pounds 300,000.
A Labour Party spokesman said: "At no stage was there a threat to the safety of the Prime Minister.
"She has been all week attempting to get as close as she could to the Prime Minister, and has been attending a number of fringe meetings."
Mrs Noel, who lives with her husband, Anthony, at Yeovil in Somerset, accused the Department of Trade and Industry of being part of a conspiracy against Lloyd's "names" - investors in the insurance market.
"I want to get my message across to Mr Blair but I promised police I would never do anything to hurt him."
She said she was stopped by policemen and security officers after the cocktail party while she was on her way back to her hotel.
"This won't stop me campaigning. I came here to protest against fraud and the way the committee of Lloyd's has conspired with the Department of Trade and Industry to cause financial hardship for thousands.
"Some people would portray me as a nutter, but that is simply not true. I am involved in true-life horror story," Mrs Noel said.
A spokesman for Mr Blair said that Mrs Noel had never managed to get closer than 20ft from him.
She has also, it has been reported, tried to chain herself to the railings outside the Palace of Westminster as part of her campaign to press Parliament for a fraud investigation into Lloyd's dealings.Reuse content