US Secretary of State John Kerry arrived in Britain on Tuesday for meetings focused on the Middle East ahead of crunch talks in Vienna this week over Iran's controversial nuclear programme.
Kerry was due to meet with British Foreign Secretary Philip Hammond later on Tuesday to discuss Iran, as well as the Ebola epidemic and tensions in Ukraine.
He will then meet with Egyptian Foreign Minister Sameh Shoukry to talk about "the next steps to try to de-escalate the situation on the ground in Jerusalem", a US official said.
Kerry will also meet with former British prime minister Tony Blair, an international special envoy to the Middle East.
Violence has been raging in Jerusalem since July, with clashes between Palestinians and Israeli forces on a nearly daily basis.
Later on Tuesday Kerry will hold talks with Oman Foreign Minister Yussef bin Alawi bin Abdullah following the latter's visit to Tehran.
He will also meet Foreign Minister Abdullah bin Zayed of the United Arab Emirates, which is taking part in US-led air strikes against the Islamic State jihadist group in Syria.
Shortly before departing for London, Kerry acknowledged the vital nature of the upcoming talks with Tehran in Vienna ahead of a November 24 deadline to reach agreement on its nuclear drive.
"We are obviously entering a key period with the negotiations regarding Iran's nuclear program, and I will go to Vienna at the appropriate moment," Kerry said at a Washington forum.
The UN Security Council's five permanent members -- Britain, China, France, Russia and the United States -- plus Germany will negotiate with Tehran on a complex comprehensive agreement that Washington hopes will prevent Iran from developing a nuclear weapons capability.
Iran's leaders insist its nuclear push serves purely civilian purposes such as energy, but many in the West fear Tehran is seeking an atomic bomb.
Republicans, who will soon control both chambers of the US Congress after elections earlier this month, have been infuriated by the tentative rapprochement of President Barack Obama, a Democrat, toward Iran.
They warn Obama is being fooled by the new, more moderate face of the Islamic republic, which aims to win billions of dollars in sanctions relief and say it will still covertly seek to develop a nuclear weapon.