By Michelle Nichols
UNITED NATIONS (Reuters) - United Nations Secretary-General Ban Ki-moon said on Thursday he had asked his Syria mediator to "focus much more to re-launch a political process" in a bid to end the four-year civil war that has killed some 220,000 people and displaced millions.
Mediator Staffan de Mistura had been working since October on a local truce in the northern city of Aleppo and announced on Feb. 17 that the Syrian government was willing to suspend its aerial bombardment and shelling for six weeks to test the plan.
But the local truce has failed to materialize. The Syrian government expelled three U.N. aid workers at the end of February and days later Syrian rebels rejected de Mistura's plan, saying it would only benefit the Syrian government.
"I have asked Staffan de Mistura now to focus much more to re-launch a political process," Ban told reporters. "I need the full support. There is no military solution. Only a political solution, dialogue, can be an answer to this."
De Mistura is due to brief the U.N. Security Council later this month.
He replaced Lakhdar Brahimi as mediator last year. Brahimi was appointed in 2012 to replace former U.N. Secretary-General Kofi Annan, who had quit after six months in the role. Brahimi and Annan both expressed frustration at the global deadlock, particularly in the Security Council, over how to end the war.
Russia, supported by China, has vetoed several Security Council resolutions threatening action against Syria, its ally.
"The international community must have full moral, political responsibility," Ban said. "The Syrian war long ago exceeded words to describe the mayhem."
Syrian troops cracked down on a pro-democracy movement in 2011, sparking an armed uprising. The United Nations said some 4 million Syrians have fled the country and an estimated 7.6 million are internally displaced.
(Editing by Jonathan Oatis)