Accepting a Palestinian state within the territories occupied by Israel in the 1967 war appears to mark a shift for Hamas, which previously had rejected any compromise over territory.
However the apparent acceptance of two states is a temporary measure, as detailed by the outgoing external leader of Hamas, Khaled Meshaal, from a news conference in Doha.
"We shall not waive an inch of the Palestinian home soil, no matter what the recent pressures are and no matter how long the occupation. We reject any idea but to liberate the home soil entirely and completely which does not necessarily mean that we recognise the Zionist entity (Israel) and therefore Hamas believes the establishment of a Palestinian state, sovereign and complete on the basis of June 4 1967 with Jerusalem as its capital and provision for all the refugees to return to their homeland is an agreeable form."
The new document uses more moderate language than the Hamas charter, written almost three decades years ago.
Hamas says its fight is with what it calls the "Zionist project" and not with Jews or the Jewish faith.
It makes a distinction between Jews who believe in Judaism and what it calls "Zionist Israeli citizens who occupy Palestinian lands."
The new document makes no mention of the Hamas's parent organisation, the Muslim Brotherhood, which is outlawed in Egypt as a terrorist group.
Some observers say the omission is designed to improve relations with Egypt and the Gulf states.
The Palestine National Initiative is a Palestinian political party that calls for a just and durable peace.
Its Secretary General, Mustafa Barghouti, welcomes the changes.
"It reflects actually a certain level of political maturity on the side of Hamas. It also provides for a much stronger foundation for Palestinian internal unity around a unified strategy around unified goals represented in the acceptance of a Palestinian state on 1967 borders. This means accepting a two-state solution."
Israel's ambassador to the United Nations, Danny Danon, says nothing about Hamas has changed.
"It's a terrorist organisation, it's committed to the destruction of the state of Israel and they are not talking about building a state alongside Israel, they talk about building a state that will replace Israel, completely. It is unfortunate, we are not buying this new charter."
David Keyes is a spokesman for Israel's Prime Minister.
He says the changes are an attempt to fool the world.
"Hamas' motivation is clearly is to alleviate some of the international pressure against it and what they are trying to do is basically fool the world to say we are not as bad as you think we are, but when you look at what they tell their own people in Arabic, on Al-Aqsa TV, on Hamas's TV stations, in their mosques, in their schools, they are calling on a daily basis to destroy Israel, they are calling on a daily basis for genocide of all Jews and this attempt to fool the world isn't going to work because it is so abundantly clear that they continue to desire the ultimate destruction of Israel."
Mustafa Barghouti says Israel's reaction shows it's afraid of peace.
"This is going to embarrass Israel a lot and we've seen the Israeli reaction which looks very frightened first of all from the possibility or the greater possibility of Palestinian unity but also the Israeli government reaction reflects fear from peace and the possibility of peace."
The announcement by Hamas comes as the President of the Palestinian Authority, Mahmoud Abbas, prepares to meet Donald Trump in Washington later this week.
