US President Donald Trump at the White House. AFP
The US diplomatic cable said countries that take "anti-Israel actions" following the conference will be viewed as acting in opposition to US foreign policy interests and could face diplomatic consequences from Washington, Reuters reported.
France and Saudi Arabia are due to co-host a UN conference next week in New York on a two-state solution to the Palestinian question.
There had been expectations that France could recognize a Palestinian state during that conference, with President Emmanuel Macron also growing increasingly frustrated with Israel's blocking of aid to the Palestinians in the war-torn Gaza Strip.
"We are urging governments not to participate in the conference, which we view as counterproductive to ongoing, life-saving efforts to end the war in Gaza and free hostages," read the US cable.
"The United States opposes any steps that would unilaterally recognise a conjectural Palestinian state, which adds significant legal and political obstacles to the eventual resolution of the conflict and could coerce Israel during a war, thereby supporting its enemies," the cable added.
Later on Tuesday, US Ambassador to Israel Mike Huckabee said the US is no longer pursuing the goal of an independent Palestinian state, marking what analysts describe as the most explicit abandonment yet of a cornerstone of US Middle East diplomacy.
In an interview with Bloomberg News, Huckabee went further by suggesting that any future Palestinian entity could be carved out of a Muslim country rather than requiring Israel to cede territory.
Last week, the French president said he expected the conference in New York would take steps "towards recognising Palestine," without giving details.
He also expressed his hopes that France's recognition of a Palestinian state would encourage other governments to do the same and that countries that do not recognize Israel should do so.
However, Macron affirmed that France would not recognize a Palestinian state alone, in a possible reference to the eagerness of Paris to see the French recognition matched by Gulf Arab allies, notably Saudi Arabia, recognizing Israel.
Several EU countries, including Ireland, Spain, and Sweden, recognize a Palestinian state. Conversely, despite backing a two-state solution, Germany said recognition now would send the wrong signal.
France is reportedly working closely on the issue with the United Kingdom, which also, so far, has not recognized a Palestinian state, AFP reported.
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