Israel’s security is of paramount importance to the White House, US Secretary of State John Kerry stressed at a joint press conference Thursday with Prime Minister Benjamin Netanyahu in Jerusalem. ”Israel’s security in this negotiation is at the top of our agenda,” he said.

“The US will do everything in our power to make certain that Iran’s nuclear program, a program of weaponization possibilities, is terminated,” Kerry added.

Both men sought to present an air of friendship and agreement after a private meeting, despite ongoing tension over Iran’s nuclear program and peace talks with the Palestinians.

Kerry aimed to reassure Israelis who might be skeptical of Washington’s commitment to their security in the wake of the interim nuclear deal forged last month between Tehran and six world powers. “I understand the challenge of security that Israel faces, I understand it very well,” he said.

Countering Israeli claims that the deal enabled Iran to advance surreptitiously toward a nuclear weapon, Kerry argued that “a peaceful program should not be that hard to prove, and everybody will know whether or not, in the end, the comprehensive agreement actually provides a test adequate to prove the peacefulness of that program.”

Netanyahu reiterated his insistence that a final deal with Iran must deny Tehran the capacity to break out to a nuclear weapon. “It is crucial to bring about a final agreement about the termination of Iran’s military nuclear capability,” he said. “I have expressed my concern since Geneva that the sanctions would begin to unravel, and I think steps must be taken to prevent further erosion of sanctions.”

But Kerry moved to reassure his host. ”The fundamental sanctions regime of oil and banking remains absolutely in place,” he said. “And we will be stepping up efforts of enforcement through the Treasury Department.”

Speaking to the Obama administration’s ongoing efforts to broker a deal between Israel and the Palestinians, and echoing an oft-repeated refrain of Netanyahu’s, Kerry emphasized Washington’s “deep, deep commitment to the security of Israel, and the need to find a peace that recognizes Israel as a Jewish state, that recognizes Israel as a country that can defend itself, by itself.”

“I believe we are making progress,” he said of the talks.

For his part, Netanyahu expressed support for the talks, saying he welcomed American involvement. ”I want to say that Israel is ready for a historic peace, and it’s a peace based on two states for two peoples,” he said. “It’s a peace that Israel can and must be able to defend by itself with our own forces against any foreseeable threat.

“We don’t need artificial crises. What we need is not grandstanding, but understanding and agreements and that requires hard and serious hard work. I’m fully committed and Israel is fully committed to such an effort and I hope the Palestinians are committed to this goal as well.”

Kerry arrived in the country Wednesday night, and according to US officials brought with him a West Bank security plan that he intends to present in meetings with Israeli and Palestinian leaders this week.

This is the US secretary’s first trip to the region since the P5+1 signed an interim agreement with Iran in Geneva late last month, a deal which has yet to be finalized but which will limit the Islamic Republic’s nuclear program for six months in exchange for sanctions relief. Israel has castigated the deal, with Netanyahu calling it a “historic mistake.”

Kerry’s visit comes at a time when the US-backed Israeli-Palestinian peace talks are ostensibly at a standstill and tensions between the Obama administration and the Netanyahu government are at an all-time high over the Iran negotiations.

Under heavy US pressure, peace talks between Israel and the Palestinians resumed in July after a three-year hiatus. Although they have continued out of the media spotlight, reports have mounted that the two sides have reached an impasse.