Israel has apologised to Joe Biden after it announced the construction of 1,600 new homes in East Jerusalem during a visit by the US vice president.
Mr Biden condemned the plan to build the new housing units on land claimed by the Palestinians as part of a future state, with the announcement coming hours after he repeated Washington's commitment to Israel.
"There is no space between the United States and Israel when it comes to Israel's security," he said after talks with Israeli prime minister Benjamin Netanyahu.
"And for that reason, and many others, addressing Iran's nuclear programme has been one of our administration's priorities."
Mr Netanyahu meanwhile praised Barack Obama for entrenching the "unbreakable" ties between the two countries since taking office last year.
But hours after those statements Israeli's interior ministry said it would be building 1,600 housing units in Ramat Shlomo, a Jewish settlement in an area of the West Bank annexed by Israel.
"I condemn the decision by the government of Israel to advance planning for new housing units," Mr Biden said in a later statement.
"The substance and timing of the announcement, particularly with the launching of proximity talks, is precisely the kind of step that undermines the trust we need right now and runs counter to the constructive discussions that I've had here in Israel.
"We must build an atmosphere to support negotiations, not complicate them."
Israeli interior minister Eli Yishai, whose department announced the construction, apologised to the vice-president, telling Israeli radio: "We had no intention, no desire, to offend or taunt an important man like the vice president during his visit.
"I am very sorry for the embarrassment. We need to remember that approvals are done according to law even if the timing was wrong. Next time we need to take timing into account."
As Mr Biden arrived on Monday Israel said it had approved the construction of 112 new apartments in the West Bank settlement of Beitar Illit, with the United Nations secretary general saying in a statement that the settlements were illegal.
About half a million Jews, including Mr Netanyahu's foreign minister, live in 100 settlements built since the 1967 occupation of the West Bank and East Jerusalem, all of which are considered illegal under international law.
The peace process has been stalled for almost 18 months, but recently the Palestinians agreed to "proximity" talks with Israel, suspending a demand Israel freeze settlement-building immediately.
Mr Biden is due to hold talks with Palestinian Authority president Mahmoud Abbas on Wednesday.
© Adfero Ltd