"The whole world knows what Hamas thinks and what our principles are," Khaled Meshaal told The New York Times in Cairo. "But we are talking now about a common national agenda. The world should deal with what we are working toward now, the national political program."
Meshaal said he envisions "a Palestinian state in the 1967 lines with Jerusalem as its capital, without any settlements or settlers, not an inch of land swaps and respecting the right of return" of Palestinian refugees to Israel.
The Fatah-Hamas reconciliation must advance peace prospects and not undermine them, Washington said after the Palestinian factions formalized their accord.
The rival parties signed an agreement in Cairo Wednesday, promising to end a four-year rift that left Palestinians under rival governments in the West Bank and Gaza Strip.
"We announce ... to our Palestinian people that we turn forever the black page of division," Fatah leader and Palestinian National Authority President Mahmoud Abbas said in a ceremony at Egypt's intelligence agency headquarters.
Fatah is the largest Palestine Liberation Organization faction. The Palestinian National Authority is the administrative organization established to govern parts of the West Bank and Gaza Strip.
Abbas promised he would soon visit Hamas-ruled Gaza, where he has not set foot since the militant Islamist group seized power in 2007 after a factional war.
The four years of division are sometimes called "Wakseh" by Palestinians, meaning humiliation, ruin and collapse as a result of self-inflicted damage.
Meshaal said many years had passed since peace negotiations with Israel began, but Palestinians are ready to give them another chance.
He said Hamas was prepared to work with Fatah in a two-pronged approach -- diplomacy and "resistance in all its forms."
U.S. State Department spokesman Mark Toner said the Obama administration would wait and see what the accord means in practical terms, but said, "It's important now that Palestinians ensure implementation of that agreement in a way that advances the prospects of peace rather than undermines them."
The Obama administration has said the new Palestinian government -- expected under the accord to be formed through parliamentary and presidential elections next year -- must recognize Israel, accept earlier agreements with it and renounce violence.
Those conditions, rejected by Hamas, were set by the United States, the United Nations, the European Union and Russia, which make up the Mideast mediation group known as the Quartet on the Middle East.