JERUSALEM -- On a day bookended by visits to the sites of Jesus' birth and death, Pope Francis on Sunday called on Palestinians and Israelis to recognize that "there is simply no other way" than a two-state solution for them to coexist peacefully after decades of conflict and bloodshed.
The pontiff repeated that message in both Bethlehem and Jerusalem on the second day of a whistle-stop tour of the Middle East that the Vatican insists is purely a religious journey.
But Pope Francis surprised observers by trying to give the moribund peace process a boost with an unexpected invitation to Israeli President Shimon Peres and Palestinian leader Mahmoud Abbas to meet him at the Vatican next month to pray for peace. The offices of the two men said that they had accepted the invitation.
"For the good of all, there is a need to intensify efforts and initiatives aimed at creating the conditions for a stable peace," the pope declared after talks with Mr. Abbas in Bethlehem, in the West Bank, on Sunday morning.
The pontiff urged officials to show courage in the attempt "to forge a peace which rests on the acknowledgment by all of the right of two states to exist and to live in peace and security within internationally recognized borders."
It was an exhortation likely to raise few objections during a three-day visit full of potential political pitfalls. But it was backed by the moral authority of a religious leader who has become one of the most respected and popular figures on the world stage since assuming the papacy last year.
In Tel Aviv, after Pope Francis arrived by helicopter from Bethlehem, Mr. Peres said Israel's hand would remain "extended in peace."
"The sacrifices of peace are preferable to the threat of war," Mr. Peres told the pope as Prime Minister Benjamin Netanyahu, a military guard of honor and clerics of various -- and colorful -- stripes looked on. Vatican and Israeli flags fluttered in the wind.
In Bethlehem, Pope Francis met privately with Mr. Abbas before celebrating Mass in Manger Square, next to the church that stands over the cave where tradition holds Jesus was born. Then, at Mr. Abbas' suggestion and in a departure from the official itinerary, the pope was driven to the north of Bethlehem to see the massive barrier that Israel has erected around much of the city, enclosing it on three sides.
In an impromptu gesture, the pontiff laid a hand on the controversial partition and said a brief prayer.
"The pope is full of surprises," said Yousef Daher, a Palestinian Christian from Jerusalem, who helped organize the papal visit to Bethlehem.
Under brilliant sunshine, thousands of worshippers greeted Pope Francis enthusiastically in Manger Square, including many Arab Christians who had journeyed to Bethlehem from the northern Israeli cities of Haifa and Nazareth, where Jesus was raised.
The pope celebrated Mass on a platform erected in front of a huge mural of the Nativity.
The pope's sermon steered clear of politics, focusing instead on one of his favorite themes: the importance of children and their welfare in a conflict-ridden world.
In spite of the avowedly religious nature of his visit, the Vatican has striven to make sure that the pope's activities in the Holy Land are politically balanced, which in the vexed context of the Mideast conflict amounts to ruffling feathers in equal measure on both sides.
Some in Israel grumbled over Pope Francis' unusual decision to land first in the West Bank before going on to Israel, a move that Palestinians eagerly seized on as affirmation of their aspiration for statehood.
But Palestinian officials were dismayed by Pope Francis' plan to become the first pontiff to lay a wreath on the grave of Theodor Herzl, the founder of Zionism, in an attempt to erase the hostility of a previous pope who refused to support the nascent movement more than a century ago.
Underscoring the political and psychological gulf separating the two sides, Pope Francis had to fly by helicopter to Tel Aviv for his official welcome in Israel rather than make the land journey of just a few miles from Bethlehem to Jerusalem, where all his appointments today are concentrated.
"Jerusalem, of course, means 'city of peace,' " Pope Francis said in his official remarks on the tarmac of Ben Gurion Airport. "Yet sadly, Jerusalem remains deeply troubled as a result of long-standing conflicts."
Mr. Peres, who at 90 will step down from the Israeli presidency in July, called Pope Francis a "modest and farsighted shepherd." He thanked the pope for standing up against anti-Semitism and assured him Israel was committed to religious freedom, a special concern of the Vatican in view of the large numbers of Christians, mostly Palestinians, who have fled the Holy Land as a result of the ongoing conflict.
Pope Francis pressed Mr. Abbas on the same point earlier in Bethlehem.