Turnbull approached at least six senior ALP figures, including former Prime Minister Bob Hawke, actively seeking their endorsement to join the ALP at the time of the republic referendum.

Speaking for the first time on the issue, Mr Hawke said Mr Turnbull approached him on November 6, 1999, at Sydney’s Marriott Hotel following the referendum’s defeat.

Mr Hawke said yesterday he remembered the conversation clearly. Mr Turnbull told him: “Bob, the only thing I can do now is join the Labor Party.”

Mr Hawke said he replied by telling Mr Turnbull “he could be accommodated” and that “the Labor Party was a broad church”.

The former senior ALP staffer David Britton, who founded the Labor lobbying firm Hawker Britton, said Mr Turnbull told him at the time of the referendum he was “deeply p….. off with Howard” – and that he had a “very different social agenda” to the then prime minister.

Mr Turnbull told Mr Britton: “Don’t you think Kim Beazley would like somebody like me as his finance spokesman?”

NSW Health Minister, John Della Bosca, was also approached by Mr Turnbull earlier that year about the possibility of securing an ALP NSW Senate seat.

At the time, Mr Della Bosca was the state secretary of the NSW Labor Party.

Senior Labor figures said Mr Turnbull raised his interest in becoming a Labor MP with the then ACTU secretary Bill Kelty as well.

While there have been previous rumblings – which have always denied by Mr Turnbull – about him wanting to the join the Labor Party, today’s revelations make it clear that his pursuit of a Labor seat was concerted and he made approaches to influential Labor figures across the party.

The various approaches by Mr Turnbull were revived in closed door discussions involving Mr Beazley and Mr Hawke at this week’s Australian-US Leadership Dialogue in Melbourne.

Mr Beazley, the Opposition leader in 1999, om 2009 confirmed he had a conversation with Mr Turnbull a year earlier at the Constitutional Convention.

Mr Beazley, who has previously made some details of the conversation public, said  that Mr Turnbull used the conversation to explore his options of getting into politics through the Labor party. Mr Beazley said he rebuffed him, telling him he “was basically a Lib” and he should join the Liberal Party if he wanted to enter Federal Parliament.

Mr Beazley also confirmed that his previous reference to another “retired senior Labor figure” Mr Turnbull had approached was indeed former PM Bob Hawke.

Mr Britton, a long-time press secretary to NSW Premier Bob Carr, said Mr Turnbull was “definitely flirting” with the idea of joining the ALP and, at the time, was also close to the “godfather” of the NSW Labor Right, “Johno” Johnson.

After raising the idea of becoming Mr Beazley’s finance spokesman, Mr Britton said he told Mr Turnbull that a Labor seat was not his to give and then referred him on to Mr Della Bosca.

Another senior figure in the republican movement told The Sunday Telegraph he also talked to Mr Turnbull about his Labor ambitions.

Tony Pooley, who now works for NSW Minister Kristina Keneally, said Mr Turnbull “had reflected on the fact he had some general discussions with Paul Keating about representing Labor federally”.

Former Labor powerbroker Graham Richardson revealed in October, 2003, that Mr Turnbull had sought a safe Senate seat from him. Mr Turnbull, seeking Liberal pre-selection for the seat of Wentworth at the time, labelled the claim a “lie”.

However, Mr Richardson this week told The Sunday Telegraph he stood by the claim. He said there were “a string of witnesses” to the half-hour meeting with Mr Turnbull, which took place in his office.