BARONESS Thatcher was today granted the honour of a ceremonial funeral at St Paul's Cathedral in the presence of the Queen, Prime Minister David Cameron and dignitaries from all around the world.

The coffin containing the body of Britain's first female prime minister was carried in military procession through streets lined by thousands of mourners and members of all three armed services.

Although the event was not the state funeral received by Sir Winston Churchill, it was conducted with more pomp and ceremony than any seen in London since the death of the Queen Mother in 2002.

A gun carriage drawn by six black horses carried Lady Thatcher to St Paul's, where a congregation of more than 2300 guests had gathered to pay their final respects.

Lady Thatcher's coffin, draped in the Union flag, bore a large bouquet of white roses with a note from children Sir Mark and Carol Thatcher reading "Beloved Mother – Always in our Hearts".

Prime Minister David Cameron said the funeral was a "fitting tribute" to a major national figure.

But protesters joined mourners lining the route of the procession, some of them angry over the reported £10million cost of the funeral.

Rows and scuffles broke out between supporters of Lady Thatcher and demonstrators outside the Royal Courts of Justice.

And it was reported that an item thrown from the crowd during the procession spooked the horses pulling the carriage.

In a journey down streets lined with mourners, the hearse bore the former prime minister's body past some of the scenes of the triumphs and setbacks of her remarkable career.

As it made its way down Whitehall under overcast skies, it passed the gates of Downing Street.

Prayers were said at the RAF church of St Clement Danes on The Strand by resident chaplain the Rev David Osborn as the coffin was transferred to a gun carriage of the King's Troop Royal Horse Artillery for the military procession.

The carriage made its way down The Strand, Temple Bar, Fleet Street and Ludgate Hill to St Paul's.

The route was lined by members of all three services in full ceremonial day dress.

More than 4000 police officers were on duty to ensure security amid heightened fears of a terror attack sparked by the bombing of the Boston marathon in the US.

As the procession moved forward, a gun salute was fired at one-minute intervals from the Tower of London.

As the procession arrived at St Paul's there was warm applause from crowds packing the pavements, along with some booing.

The eight pall-bearers who carried the casket into the Cathedral were drawn from Army units, Royal Navy ships and RAF stations with links to the Falklands war.

Lady Thatcher's grandchildren Michael and Amanda walked ahead of the coffin as it entered the cathedral.

The Queen and Duke of Edinburgh headed a glittering list of dignitaries from around the world, former colleagues and showbusiness stars attending the funeral, including Mr Cameron and all members of his Cabinet, as well as more than 30 members of Lady Thatcher's cabinets from 1979 to 1990.

Around 170 countries were represented by dignitaries, including two heads of state, 11 serving prime ministers, members of royal families, foreign ministers and ambassadors.

But there were no serving ministers from either the US or French administrations.

Former US vice-president Dick Cheney and ex-secretary of state Henry Kissinger were there in a personal capacity.

At the former prime minister's request, the funeral was being framed by British music, with pieces by UK composers played at the beginning and end of the service.

Lady Thatcher chose the hymn He Who Would Valiant Be, while the Charles Wesley hymn Love Divine, All Loves Excelling will reflect the influence of her Methodist upbringing, and the final hymn will be the patriotic verse I Vow To Thee My Country.

The organ played Psalm 84, set to the music of Johannes Brahms, which is the same piece Lady Thatcher chose to be played at the funeral of her husband Sir Denis Thatcher in 2003.