It was just 67 words written in a faraway country a century ago, but it shaped their lives, Israelis and Palestinians say.

Thursday marks the 100th anniversary of the Balfour Declaration, when the British government said it viewed "with favour the establishment in Palestine of a national home for the Jewish people".

The anniversary is a joyous occasion for Israelis, the precursor to the creation of their state in 1948, with the declaration encouraging Jews to emigrate to the land of their ancestors.

Michael Oren, an Israeli deputy minister, recently called it the "high-water mark of Zionist diplomacy."

For Palestinians, however, it marks the beginning of a catastrophe -- arguably leading to hundreds of thousands fleeing or being forced from their homes during the war surrounding Israel's creation.

It is also seen as having helped sow the seeds of the Israeli-Palestinian conflict and Israel's ongoing 50-year occupation of the West Bank.

Small numbers of Jews, including those having fled anti-Semitic persecution elsewhere, lived on the land before 1917 alongside Palestinian communities.

Zionist leaders were encouraging mass immigration as part of efforts to fulfil their dream of a Jewish state in the land from where their ancient ancestors fled.

But the open letter penned by British foreign secretary Arthur James Balfour provided new impetus for the push.

Baruch Levy's parents left Iraq for Mandate Palestine in 1934, cradling him in their arms. He had been born the year before in Baghdad.

"My parents were Zionist, religious people. They came here I believe following the Balfour Declaration... after the First World War when the British took over," he said.

"That gave them and other communities a kind of push to come."

Relations between Jewish and Palestinian communities had never been perfect, but they worsened as the British mandate in Palestine following World War I wore on, he said.

Levy remembers fighting between the communities from time to time.

"The Jewish goal was from the very beginning building the Jewish home," he said.

"The Arabs, as I see it, were always kind of an obstacle, or putting obstacles to us as Jewish people."

Levy said he remembers the anniversary of Balfour as a day of celebration for Jewish communities.

"As a child we always celebrated the second of November in schools, in streets, in youth movements. It was like the beginning of something."

- 'Destroyed our world' -

Palestinians see it differently. 

Mohammed Hilleyel, 94, was born only six years after the letter prescribed a future for the land he came from, but he was not to know of its existence for more than two decades.

While the decision was published in the British press in 1917, Hilleyel said there was no real effort to inform Palestinians living on the land during the British mandate period that ended in 1948, when the state of Israel was founded.

It was only in 1946, two years before he and his family would have to flee their farmlands near Jaffa and eventually end up in Gaza, that they learned of the British declaration from a military officer.

When told of what in Arabic is called the Balfour promise, he says he was shocked. The British, he said, "destroyed our world".

"What is Britain to me? It's the Balfour agreement."

Other Palestinians, especially in larger cities, did know, and Rima Tarazi, born in 1932, said there were regular protests against British policies during the mandate era.

Despite this thousands of Jews arrived in mandate Palestine during the British period, and Tarazi accused the British of unfair treatment.

"There was no right or justice in the whole Balfour Declaration. How did they have the right to give somebody's land to somebody else? I could never understand that."

She said the declaration has "haunted" the Palestinian people for 100 years.

Despite worsening relations as the British mandate worn on, Tarazi remembers they had Jewish neighbours, the Eisenbergs, whom they were close to. 

During World War II as word of atrocities against Jews came out of Germany, the family's mother came to speak to Tarazi's.

"She told her 'If the Nazis ever came here will you promise me to take care of Batia my daughter as your daughter?' My mother said 'of course.'"