Margaret Thatcher thought Edward Heath was gay, a new biography by Charles Moore has claimed.

In ‘Margaret Thatcher The Authorised Biography’ Moore records a note that Bill Deedes, the former Tory minister and then editor of the Daily Telegraph, made after a conversation with Thatcher in 1976:

“M. seems convinced TH [Ted Heath] is a homosexual. (Women have more accurate instincts than we.) I said charitably: ‘an instinct sublimated in boats’.”

In an interview in 1974, before she challenged him for the leadership, Thatcher referred to Heath not having a family.

Moore says it is “possible” she was deliberately hinting he was gay, in order to discredit him.

Thatcher – who died earlier this month aged 87  – succeeded Heath as Conservative Party leader in 1975 and the two were bitter rivals.

Speculation has always surrounded the private life of Heath, who died in July 2005 aged 89.

In 2007, Brian Coleman, the gay former Conservative London Assembly Member and ex-mayor of Barnet, claimed Heath was warned by police to stop cruising for sex as part of a vetting process in 1955.

That year he became a privy councillor and chief whip under Prime Minister Anthony Eden.

However, Conservative MP Sir Peter Tapsell, who became an MP in 1959, dismissed the claims.

“I knew him well and would be astonished if he was a practising homosexual,” Sir Peter told the Mirror in 2007.

Sir Edward’s successor as MP for Bexley and Old Sidcup, Derek Conway, who left the Commons in 2010, said: “Ted was wedded to politics. He didn’t have a great deal of companionship but there are people capable of getting on with their lives without companionship.”

As prime minister from 1979-1990, Margaret Thatcher was the embodiment of social conservatism.

Although she was capable of showing tolerance towards homosexuality on an individual level by appointing closeted gay members to her government, LGBT debate following her death has centred on her role in passing Section 28 – legalisation which banned the “promotion” of homosexuality in schools.

Section 28 was later repealed under Tony Blair’s Labour government and the current Conservative Prime Minister, David Cameron, apologised for the policy in 2009.