United Nations Secretary-General Ban Ki-moon reiterated his belief in a two-state solution to the Middle East peace process on Tuesday, but was coy when commenting on the current Palestinian campaign to win nonmember state status at the UN.

“A two-state solution remains the only viable option to end this conflict and the occupation that has endured for almost half a century,” Ban said during a talk at Yale University. He made no direct reference to Palestinian Authority President Mahmoud Abbas’s declared intention to seek upgraded nonmember status for “Palestine” at the UN General Assembly later this month.

“The cost of the continued stalemate and ongoing illegal settlements continues to rise with each passing day – and each missed opportunity,” he added. “As I have warned repeatedly, without strong leadership by the parties and the international community, the two-state solution, and the commendable institution-building achievements of the Palestinian Authority, are in jeopardy.”

Talks between Israel and the Palestinians have been stalled since 2010 over disagreements on the terms for starting negotiations.

“I once again appeal to all those with influence: the Middle East peace process is on life support,” he continued. “Do not pull the plug. Breathe new life and hope now. The region and the world cannot wait.”

The secretary-general avoided offering an opinion on the Palestinian bid to become a nonmember state at the UN, saying only that  “such matters are solely in the hands of Member States.”

The Palestinians have set November 29th as the day they will ask the UN General Assembly to vote on upgrading their status from “observer” to “nonmember state”.

The unilateral move is opposed by Israel and the United States that prefer to restart negotiations.

Israel on Wednesday threatened to abandon the 1993 Oslo Accords and to topple the Palestinian Authority if the UN votes in favor of the Palestinian bid.

The Palestinians failed to obtain full membership at the UN in 2011 due to a lack of support in the Security Council. No member has veto power in the General Assembly and a resolution submitted by Abbas is almost certain to be approved by the world body, which is dominated by countries sympathetic to the Palestinian cause.

The upgraded UN status would add weight to Palestinian claims for a state in the West Bank, Gaza Strip and East Jerusalem, territories captured by Israel in the 1967 Six Day War. Israel pulled out of Gaza in 2005.

The Palestinians also hope to use their upgraded status to join additional UN bodies, such as the International Criminal Court, where they could attempt to prosecute Israel.