The White House on Friday urged Yemeni President Ali Abdullah Saleh to begin a "full transfer of power," hours after his return to the country amid protests for reform by dissidents.

The United States also condemned "the use of power" against demonstrators, and urged a "political solution" to resolve the conflict raging during Saleh's three-month stay in Saudi Arabia, White House spokesman Jay Carney told reporters.

Saleh had returned home from Saudi Arabia on Friday to "prepare for elections," a senior Saudi official told AFP on condition of anonymity.

US officials, however, said Washington's view "hasn't changed," as they called on the Yemeni leadership to step aside.

"We want to see Yemen moving forward," State Department spokeswoman Victoria Nuland said in a statement.

"Whether president Saleh is in or out of the country, he can make this happen (by) stepping down from power and allowing for the country to move on," she said.

The 69-year-old Saleh has faced mass protests against his rule since January. He had flown to Saudi Arabia for treatment over blast wounds he received in a bombing on his compound.

Upon his return Friday, he called for a truce and talks to end the crisis.

The soaring violence has raised long-standing fears that Yemen, which faces a Shiite rebellion in the north and a separatist movement and the growing influence of Al-Qaeda in the south, is heading for full-blown civil war.

The UN High Commissioner for Human Rights Navi Pillay warned Thursday that Yemen was at a "dangerous crossroad."