Roland Oliphant: Behind the fine print of the deal at Minsk
The talks have produced two documents: a joint statement that sets intentions and broad objectives, and a more detailed 13-point Russian-language document entitled 'A Complex of Measures for Fulfilment of the Minsk Agreement'.
The joint statement, adopted by Vladimir Putin, Petro Poroshenko, Angela Merkel and Francois Hollande, commits their respective countries to respect Ukrainian territorial integrity and seek a diplomatic solution to the crisis based on the original Minsk agreement signed in September.
France and Germany also promise to offer assistance in restoring the banking system in the conflict area of eastern Ukraine, which should provide significant economic relief to local people.
And all countries support trilateral talks between Russia, Ukraine, and the European Union to ensure gas deliveries and allay Russian concerns over the EU association agreement with Ukraine.
It was former president Viktor Yanukovych's rejection of that agreement under Russian pressure that sparked the revolution that led to the current crisis.
But the really interesting stuff is in the second document, which lays out time tables and step-by-step conditions for the implementation of a peace deal. The first step is a general ceasefire from midnight tomorrow. That is to be followed two days later by a withdrawal of heavy artillery and rocket systems from the front line.
Ukrainians are obliged to complete the withdrawal from the current line of contact, and the separatists from the original line agreed at the previous ceasefire in Minsk in September, within 14 days of the ceasefire.
Next comes a full prisoner exchange, with both sides committed to freeing all hostages and POWs within five days of the withdrawal of heavy weaponry.
Mr Poroshenko said he had secured agreement for the release of Nadiya Savchenko, a Ukrainian army helicopter pilot who is being held in a Russian prison on charges of murdering two Russian journalists in the war zone.
Ms Savchenko has become an icon of resistance in Ukraine, and has been on hunger strike for over 60 days in protest at what she says are fabricated charges. Securing her release is a victory that will help Mr Poroshenko sell this deal to the Ukrainian public. Previous efforts to organise ceasefires and prisoner exchanges have only been partially successful.
Even trickier is the political settlement - including a large slice of autonomy for the rebels, withdrawal of foreign (ie. Russian, though that word is not used) troops, and restoration of Ukraine's control of its border with Russia. The mechanism outlined in the document is complex, delicate and riddled with opportunities for either side to baulk or accuse the other of non-compliance.
First, the Ukrainian parliament has 30 days in which to reinstate a law granting special status - including more autonomy - to the eastern regions at the centre of the war.
Under that law, local elections must be organised in consultation with the defacto - ie. separatist - authorities in the Donetsk and Luhansk regions. Next, Ukraine must pass sweeping constitutional reforms devolving significant power to the regions, including the right to raise their own police forces, chose an official regional language (this is designed to protect Russian language rights), and conclude cross-border deals with neighbouring regions of Russia. The central government will continue to fund the regions and restore banking services.
This is good news for the long-suffering civilians of the Donbass. Many have been left destitute and on the brink of starvation since Kiev cut off the banking system, pensions, and state-sector salaries in November, and the separatists have singularly failed to establish a functioning state to replace such services.
Ukraine has until the end of this year to pass those reforms. Only then will it be allowed to restore full control of its border with Russia.
But the text is rife with opportunities for disagreement and worse.
If Ukraine really seals its borders, the separatists will be left incredibly vulnerable. They, and their Russian backers, may baulk at actually implementing that part of the deal. Similarly, although the agreement calls for the withdrawal of "foreign armed units, military equipment, and also mercenaries" from Ukrainian territory under OSCE observation, no deadline is set for such a withdrawal.
Nor does this document address the fundamental geo-political quarrel that sparked the war: Russia's deep-seated opposition to Ukraine's alignment with the European Union and Nato expansion. (© Daily Telegraph, London)