U.S. President Barack Obama's point man in the Middle East is on a new peace mission.
U.S. envoy George Mitchell launched a fifth round of indirect peace talks between Israel and the Palestinians. He admitted that progress does not come easy.
"We recognize it is difficult; there are obstacles; there will be setbacks. But our determination remains," he said.
The latest setback was a comment by Israeli Foreign Minister Avigdor Lieberman, a day before Mitchell launched his new peace mission.
On Tuesday, Lieberman said there is "no chance" of establishing a Palestinian state by 2012, throwing cold water on the stated goal of international mediators.
But Mitchell said the United States will press on toward the two-state solution.
"We will continue until that vision is achieved for the simple reason that it is in the interest, we believe, of the people of Israel, the Palestinian people and all the people of the region, and it is in the interest of the United States," said Mitchell.
Mitchell toured an Israeli border crossing for a first-hand look at how Israel has eased its blockade on the Gaza Strip. Israel is allowing all food supplies and some building materials into Gaza in the wake of the deadly raid on an aid flotilla a month ago. Nine pro-Palestinian activists were killed when Israeli commandos stormed the ships, sparking international outrage and fresh demands for Israel to ease the blockade.
Mitchell commended the easing of the blockade.
"The situation in Gaza was unsustainable and demanded fundamental change. We welcome these changes. These arrangements should significantly improve conditions for Palestinians in Gaza," he said.
Mitchell also demanded the release of a captive Israeli soldier who has been held for four years in Gaza by the ruling Islamic militant group Hamas.