For many of Margaret Thatcher's admirers, the war she fought with Argentina over the Falkland Islands was her finest moment -- and there will be many reminders of the brief but bloody conflict at her funeral on Wednesday.

Guns used in the 1982 war will be fired into the skies over London as the former British premier's coffin is led to St Paul's Cathedral, through streets lined by 700 soldiers, sailors and airmen.

Members of regiments that fought in the South Atlantic will carry the coffin into the cathedral, where Falklands veterans are joining the 2,000 world leaders, celebrities, friends and colleagues invited to the Iron Lady's high-profile farewell.

The 74-day war for the islands -- which have been held by Britain since 1833 and are claimed by Argentina -- cost 649 Argentine and 255 British lives.

It also saved Thatcher's political career -- catapulting her from deep unpopularity to a landslide second election win in 1983 after British troops recaptured the windswept islands from Argentine forces.

"The Falklands were absolutely key to her political fortunes, a real turning point for Mrs Thatcher," Eliza Filby, lecturer in modern history at King's College London, told AFP.

"She was politically vulnerable on the eve of the Falklands war. In terms of poll ratings she was the most unpopular post-war prime minister."

The funeral's strong military theme reflects her deep gratitude and respect for the armed forces, said Filby, whose book "God and Mrs Thatcher" is published later this year.

"In a time of political crisis, the ones that saved her were not her cabinet -- it was the military. There's little doubt that if the Falklands had gone wrong at any level -- mass casualties, defeat -- she would have been out."

-- 'It made her into the Iron Lady' --

Argentina's shock invasion of the Falklands on April 2, 1982 could not have come at a worse time for Thatcher's Conservative government.

Three years after she came to power, unemployment was spiralling and inflation was still sky-high.

Riots had broken out in 1981 in the south London neighbourhood of Brixton and in the northwestern city of Liverpool.

Public anger simmered further still when news came that her government had allowed Argentina's then-ruling military junta to invade a British colony.

It was make or break time for the prime minister. Three days after the invasion she sent a task force of over 100 ships to reclaim the islands, 13,000 kilometres (8,000 miles) from the British mainland.

"What was the alternative?" she wrote in her memoirs. "That a common or garden dictator (Argentine president Leopoldo Galtieri) should rule over the queen's subjects and prevail by fraud and violence?

"Not while I was prime minister."

Argentina surrendered on June 14. It was a defining moment for Britain's first and only female prime minister.

"It really made her into the Iron Lady," said Filby.

"She was resolute, and that became her signature image," she said, citing Thatcher's defeat of the coal miners' year-long strike in 1985, and her tough stance on Europe, as further examples of this famously uncompromising style.

Thatcher claimed the victory delivered a massive confidence boost to a nation that was seen as having a diminishing role on the world stage.

"We have ceased to be a nation in retreat," she told a Conservative rally in July 1982.

"Britain found herself again in the South Atlantic and will not look back from the victory she has won."

-- Rising tensions over the islands --

There was an outpouring of tributes from the Falklands' 3,000 residents following Thatcher's death from a stroke on April 8 at the age of 87.

Wednesday will be a public day of mourning on the archipelago, and there have even been calls to rename the tiny capital Stanley in her honour.

"The Falkland islanders will forever remember what Margaret Thatcher did for the islands," Barry Elsby, a doctor and member of the Falklands' legislative assembly, told AFP.

"Without Margaret Thatcher's intervention and having the courage to take what was a very difficult decision, the Falkland Islands would now be a colony of Argentina."

Tensions over the islands have flared again in recent years, with Argentina particularly enraged by Britain's opening of the surrounding waters to oil exploration.

Argentina's President Cristina Kirchner -- who has not been invited to Thatcher's funeral -- has pressured Britain to negotiate over the Falklands' sovereignty.

The islanders voted 99.8 percent in favour of staying British in a referendum last month, but Argentina rejected the vote as meaningless.

Thatcher's Falklands-themed funeral could be interpreted as a provocative move at this time of heightened tension, according to Victor Bulmer-Thomas, a Latin America expert at the Chatham House think-tank.

"But they don't mind being provocative to Argentina at this particular moment, because they think that Argentina is being provocative to Great Britain," he said.