The brief ceremony at Abbas' West Bank headquarters was preceded by last-minute haggling over the makeup of the 17-member Cabinet of technocrats, signaling continued tensions between the long-time rivals.
The Islamic militant Hamas, which seized the Gaza Strip from Abbas' Fatah in 2007, had demanded that he reverse a decision to remove the position of minister of prisoner affairs from the government. Hamas officials announced just minutes before the start of the swearing-in ceremony that the dispute had been resolved, though the nature of the compromise was not immediately clear.
After the 2007 takeover of Gaza, Hamas set up its own government there, leaving Abbas with only the autonomous areas of the West Bank. Abbas considered the loss of Gaza as a stain on his presidency.
"Today, we declare the end of the split and regaining the unity of the homeland and the institutions," Abbas said in a recorded speech broadcast after the swearing-in ceremony on Palestine TV.
Hamas expressed similar sentiments.
"We can say the division is behind us now," said Sami Abu Zuhri, a Hamas spokesman in Gaza, adding that the Palestinians "have major challenges ahead of us to erase the traces of division."
The new Cabinet is to be temporary and prepare for general elections in 2015, though there are signs that neither side is eager to seek such a vote soon.
