The agreement, reached after seven hours of negotiation in Geneva, requires all sides to refrain from violence, intimidation or provocative actions. It calls for the disarming of all illegally armed groups and for control of buildings seized by pro-Russian separatists during the protests to be turned back over to authorities.
It also gives amnesty to protesters who comply with the demands, except those found guilty of committing capital crimes.
Monitors with the Organization of Security and Cooperation in Europe will be tasked with helping Ukraine authorities and local communities comply with the requirements outlined in the agreement. And Kiev's plans to reform its constitution and transfer more power from the central government to regional authorities must be inclusive, transparent and accountable - including through the creation of a broad national dialogue.
The tentative agreement could put on hold - for now at least - economic sanctions the West had prepared to impose on Russia if the talks were fruitless. And that would ease international pressure both on Moscow and nervous European Union nations that depend on Russia for their energy.
Russian President Vladimir Putin criticized the U.S. and its European allies for having what he called a double standard and said he hoped he would not have to deploy troops to Ukraine.
Ukraine was hoping to use the Geneva talks - the first of their kind over the crisis that threatens the new government in Kiev - to placate Russia and calm hostilities with its neighbor even as the U.S. prepared a new round of sanctions to punish Moscow for what it regards as fomenting unrest.
Meanwhile, Russia was honing a strategy of its own: Push the West as far as possible without provoking crippling sanctions against its financial and energy sectors or a military confrontation with NATO.
In a television appearance in Moscow on Thursday, Putin denied claims that Russian special forces were fomenting unrest in eastern Ukraine. He called the Ukrainian government's effort to quash the uprising a "crime."
In Washington, Defense Secretary Chuck Hagel said the U.S. would send non-lethal assistance to Ukraine's military in light of what he called Russia's ongoing destabilizing actions there. He told a Pentagon news conference that the military assistance to Ukraine will include medical supplies, helmets, water purification units and power generators.
Ukraine has asked for military assistance from the U.S., a request that was believed to include lethal aid like weapons and ammunition. Obama administration officials have said they were not actively considering lethal assistance for fear it could escalate an already tense situation.
The U.S. has already sent Ukraine other assistance, such as pre-packaged meals for its military.
In Brussels, NATO chief Anders Fogh Rasmussen said the military alliance would increase its presence in Eastern Europe, including flying more sorties over the Baltic region west of Ukraine and deploying allied warships to the Baltic Sea and the eastern Mediterranean. NATO's supreme commander in Europe, U.S. Air Force Gen. Philip Breedlove, told reporters that ground forces also could be involved at some point, but gave no details.
Officials said a full-scale Russian invasion of eastern Ukraine would result in broad U.S. and European sanctions on key Russian economic sectors, including its powerful energy industry. However, European nations are divided on whether to limit its access to Russia's oil and gas supplies, and a vote to sanction must be unanimous among the EU's 28 member states.
The sanctions that could be levied in the aftermath of the Geneva meeting were expected to focus on Putin's close associates, including oligarchs who control much of Russia's wealth, as well as businesses and other entities they control. It was unclear whether those sanctions would change Putin's calculus, given that the U.S. and the Europeans already have launched targeted sanctions on people in Putin's inner circle.
AP White House Correspondent Julie Pace, AP National Security Writer Robert Burns and AP Diplomatic Writer Matthew Lee in Washington, AP Writer Lori Hinnant in Paris and AP Television News Senior Producer Ed Brown in Geneva contributed to this report.