US issues Palestinian territories security alert
The embassy advised its citizens living or travelling in the West Bank or Gaza to "maintain a high level of vigilance" and "increase their security awareness".
"Violence can occur with little or no warning," said the alert published on the embassy's website.
It mentioned checkpoints, markets, tourist sites and transportation hubs among a list of possible targets for attacks, but did not detail a specific threat to a location or to American citizens.
"US citizens should carefully consider risks to their personal safety and security when considering visits to sites and events that are potential targets," the embassy added.
The warning follows a pledge by Israeli Prime Minister Benjamin Netanyahu to annex parts of the West Bank, as outlined in a peace plan drawn up by Washington.
Israel has controlled the West Bank since seizing it in the 1967 Six-Day War."This is an opportunity which we shall not allow to pass by," Netanyahu said on Monday.
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The country's new government may table legislation to begin annexation as soon as 1 July, despite strong opposition from neighbouring Jordan and the broader international community.