How about a cease-fire, guys? Photographer: Andrey Kronberg/AFP/Getty Images
How about a cease-fire, guys? Photographer: Andrey Kronberg/AFP/Getty Images

Russia has responded to the imposition of tougher U.S. and European sanctions by piling up troops and munitions at the Ukrainian border. This is not evidence that sanctions were the wrong strategy or that they didn't work -- they are still the right move for the long term. At the moment, though, more creative thinking is needed to halt the escalation of hostilities.

It won't be easy. The scope of the standoff over Ukraine is too great for Russia and the West to achieve any grand settlement quickly. Such a deal will take time and goodwill, both of which are now in short supply.

Unrest in Ukraine

This week's emergency meeting of the United Nations Security Council provided an example of how not to cool things down. Russia, which called the special session, declared that the Ukrainian military had perpetrated a civilian "catastrophe" in Donetsk and Lugansk, and called for the creation of humanitarian corridors to bring in food and medical aid. No doubt concerned that Russia was preparing the diplomatic ground to invade, under the guise of a "humanitarian" intervention, Ukraine said no such crisis exists. The U.S. said there was not even a need for the Security Council meeting.

By pushing back in this way, however, Ukraine and the U.S. ignore the rising tension with Russia and what's needed to bring it down. President Vladimir Putin cannot afford to be perceived at home as losing in Ukraine. The new European and U.S. sanctions and the recent success of the Ukrainian military operation are forcing him to consider a greater armed intervention. Yet he knows that if he chooses this path, it would trigger still tougher sanctions and could involve him in a long and unpredictable war. That's an unattractive set of options, but without some third way between capitulation and escalation, Putin is likely to choose the latter.

As Georgia and Moldova can attest, once armed Russian "peacekeepers" enter a country, they are impossible to remove. Ukraine would spend the coming decades struggling to retrieve its lost territories and worrying conflict might reignite.

So how to find Putin an offramp? One possibility is to agree with him that a humanitarian crisis exists in eastern Ukraine and needs to be addressed. With an official UN tally of 1,367 dead, 117,000 displaced internally and as many as 740,000 fleeing to Russia, that's hardly a stretch. Rather than just accuse Putin of stoking conflict, why not offer to form an international peacekeeping force, under the authority of the UN or the Organization for Security and Cooperation in Europe?

Modeling such a force would admittedly be hard, not least because it would have to include a Russian contingent and a cease-fire would have to be in place. Putting heavily armed Russian troops in control of territory on their own border would be difficult for Ukraine to accept, so the extent to which the peacekeepers were armed would also need to be negotiated.

Both Russia and the West have the leverage to push a cease-fire. Although the rebels have refused to lay down their weapons in the past, they know that if Putin were to withdraw support they would collapse within weeks. Ukraine would no doubt also resist, thinking its armed forces are on a roll and can secure a military solution. Ultimately, they can't, however, with Putin there to ensure the rebels are not wiped out. The U.S. and the European Union, whose aid is keeping Ukraine out of bankruptcy, can persuade the government in Kiev to play ball.

A peacekeeping force could stop the bloodshed and freeze the status quo, ideally allowing some time for everyone concerned to begin to address the issues at the heart of the Ukraine crisis: Putin's determination that Ukraine should join his Eurasian Union and the Ukrainians' preference to integrate with the EU.

There are certainly risks to such a strategy: The peacekeeping force would have to be assembled quickly, to keep Russia from pre-emptively sending in troops to "prepare the ground." The force would probably need to exclude U.S. troops, to minimize the Russian antagonism, and the right balance between Russian and European monitors would have to be carefully negotiated.

These risks would be worth taking if saying "yes" to Putin's peacekeeping force would allow him to escape a costly choice for Russia and declare a small victory at home. It might also create the time for a settlement that would allow Ukraine to remain a bridge between Russia and the West, rather than a battleground.

To contact the senior editor responsible for Bloomberg View's editorials: David Shipley at davidshipley@bloomberg.net.