Palestinian President Mahmoud Abbas is threatening unspecified legal action against Israel if Prime Minister Benjamin Netanyahu fails to comply with four Palestinian demands, including a freeze on settlement expansion in the West Bank, and the acceptance of the 1967 borders plus land swaps as a basis for negotiations between the two sides.

The ultimatum is contained in a letter Palestinian officials handed Netanyahu earlier today, a copy of which was obtained by The Daily Beast. People familiar with the thinking behind the letter said the legal action would likely include another United Nations membership bid and possibly a petition to the International Court of Justice.

Drafts of the letter had been labored over for some weeks by Palestinian officials, who in private conversations had said it would include a dramatic announcement. While the text accuses Israel of effectively stripping the Palestinian government in the West Bank of powers, Abbas stops short of threatening to dismantle his administration—an idea that has been discussed during the writing of the letter.

“Should the Government of Israel refuse to honor these above-referenced obligations, we will seek the full and complete implementation of international law as it pertains to the powers and responsibilities of Israel as occupying power in all of the occupied Palestinian territory,” says the text, which runs to three pages.

An Israeli official confirmed Netanyahu received the letter and said he would respond within two weeks.

The correspondence comes amid one of the longest droughts in diplomacy between the two sides since their landmark Olso accord in 1993. Though negotiators have had sporadic contacts over the past few months, there have been no sustained negotiations since 2009.

Netanyahu has made repeated offers to meet Abbas but the Palestinian leader says he’ll renew the peace process only after Israeli stops building new homes for Jews in the West Bank, which Israel has occupied since 1967.

The letter also demands Israel release all Palestinian prisoners and “revoke all decisions taken since 2000 which undermine agreements signed between Israel and the PLO”—an apparent reference to the troop positioning in the West Bank.

“Twenty years ago, we concluded with Israel an agreement under international auspices which was intended to take the Palestinian people from occupation to independence,” Abbas writes.

“Now, as a result of actions taken by successive Israeli governments, the Palestinian National Authority no longer has any authority, and no meaningful jurisdiction in the political, economic, social, territorial and security spheres. In other words, the P.A. lost its reason d’être.”

Gesturing at Israel’s security concerns, Abbas says in the letter that violence and terror committed by both sides is “not the way.”

“I know that it erodes both of our public’s trust in peace. Therefore, I reiterate our full commitment to a policy of zero tolerance against violence.”

“At the same token, I expect your understanding that settlement building is eroding the Palestinian trust in your commitment to reconciliation and the idea of the two states solution. The logic is simple: If you support the establishment of a Palestinian state, why do you build on its territory?”

One source familiar with the details said the letter was a watered down version of previous drafts, which contained more specific ultimatums.

The source said Abbas’s renewed membership bid with the U.N. would be channeled through the General Assembly, where Palestinians are likely to get a majority, and would probably take place in the coming months. The move would serve to isolate Israel but would likely have few practical consequences.

A previous gambit at the Security Council last year got bogged down over America’s threat to use its veto power.