At a conference in the Cuban capital, Havana, marking the 40th anniversary of the missile crisis, delegates have said that they were much closer to nuclear war than had previously been thought.

Studying newly declassified documents, Cuban, American and Russian protagonists in the events of 1962 were told that on 27 October a US navy destroyer dropped depth charges off the Cuban coast almost accidentally hit the hull of a Soviet submarine carrying a nuclear warhead.

This was not only the most dangerous moment of the Cold War. It was the most dangerous moment in human history

Arthur Schlesinger Historian and Kennedy aide

The US military "did not have a clue that the submarine had a nuclear weapon on board," Thomas Blanton, director of the National Security Archives said.

"They exploded right next to the hull," Vadim Orlov, the submarine's signals intelligence officer, said in a written account of the incident.

At first, submarine crew members considered using the nuclear weapon, thinking that war had erupted, Mr Orlov wrote in his account. But ultimately the craft surfaced.

Looming war

Politicians, military figures and academics from Cuba, Russia and the United States are participating in the three-day event.

Cuban leader Fidel Castro, dressed in a black suit and tie, joined the former US Defence Secretary, Robert McNamara, to discuss what is known in Cuba as the October Crisis.

	:	Cuban missile crisis
Click here for pictures of the stand-off

The organisers, from George Washington University, say that with the prospect of war against Iraq looming, the diplomacy shown in 1962 could offer lessons to today's leaders.

Mr McNamara said: "It was the best managed foreign policy crisis of the last 50 years."

He credited Mr Castro, former US President John F Kennedy and Soviet Premier Nikita Khrushchev for ensuring the world was saved from nuclear destruction.

Many of those attending are meeting for the first time - including Mr McNamara, Soviet Deputy Foreign Minister Georgi Konyenko, and senior Cuban generals.

The missile crisis is widely seen as the closest the world has ever come to nuclear war.

Delegates

Soviet: Missile deployment planner General Anatoly Gribkov, Sergei Mikoyan, son of Anastas Mikoyan, Soviet deputy premier at the time of the crisis US: Kennedy speechwriter Theodore Sorensen, historian Arthur Schlesinger, Robert Kennedy's widow Ethel, former CIA analyst Dino Brugioni (who spotted the missile sites) Cuba: Fidel Castro, Cuban generals involved in crisis

On the morning of 15 October 1962, a US spy plane spotted Soviet missiles being deployed in Cuba - leading to 13 days of heated exchanges between John F Kennedy and Nikita Khrushchev, with war looking increasingly likely.

Then, on 28 October, the Soviets agreed to withdraw, as long as the US did not invade Cuba.

As part of the conference, delegates will visit a former missile silo at San Cristobal in western Cuba.

What are you memories of the time? Did you live in fear of a nuclear exchange?

A selection of your e-mails will be published on Monday 14 October.

Send us your comments: Name: Your E-mail Address: Country: Comments:

Disclaimer: The BBC will put up as many of your comments as possible but we cannot guarantee that all e-mails will be published. The BBC reserves the right to edit comments that are published.