WASHINGTON - Secretary of State John Kerry said today all the conditions are ripe for successful negotiations for both halting Iran's nuclear program and reaching peace between Israelis and Palestinians.

Addressing the annual American-Israel Public Affairs Committee (AIPAC) Conference, Kerry said it was time to "seize the diplomatic moment" and remain at the negotiating table with all parties as long as possible.

Kerry said that tough sanctions had brought Iran to the negotiating table, and that it was time now to exhaust the possibility of a diplomatic solution to Iran's desire to enrich uranium and plutonium.

"It is crucial that we seize what might be the last best chance to have diplomacy work," Kerry said, adding that if a good-faith effort at negotiation fails, it will provide justification for more forceful options if necessary.

On the Middle East peace process, Kerry said President Obama and he were committed to a solution, and suggested they found equally willing partners in Israeli Prime Minister Benjamin Netanyahu and Palestinian Authority President Mahmoud Abbas.

He also addressed criticism by some Israeli hard-liners that he is driven by a misguided, "messianic" desire to achieve peace.

"It just strikes me as the wrong question to ask, why do I go," Kerry said. "This isn't about me. This is about the dreams of Israelis and the dignity of Palestinians."

Right after his speech, Kerry departed for a flight to Kiev, Ukraine, where he will meet with members of the transitional government Tuesday.