BRUSSELS -- When the so-called Minsk II deal was signed on February 12, everyone knew its implementation would be -- in the words of Ukrainian President Petro Poroshenko -- "very difficult."

Now, nearly two weeks later, the agreed cease-fire is sketchy at best. Russia-backed separatists have taken the strategic rail hub of Debaltseve and continue to press against areas around the city of Mariupol. NATO's top commander, U.S. General Philip Breedlove, said on February 20 that "it is a cease-fire in name only."

The agreed withdrawal of heavy weapons is haltingly under way but with significant delays and inadequate monitoring by the Organization for Security and Cooperation in Europe (OSCE).

But if a consensus emerges that Minsk II is dead, what would the consequences be and what comes next?

The European Union continues, officially at least, to place its hopes on the Minsk II agreement. Maja Kocijancic, spokeswoman for EU foreign policy chief Frederica Mogherini, says flatly: "The Minsk agreement is the agreement that we have."

When pressed to comment on the spotty cease-fire and other signs the Minsk II agreement is not working, Kocijancic said "that only makes the need to try harder even more urgent."

"What we desperately need is to see a cease-fire and this is what we are pushing for," Kocijanicic told RFE/RL on February 24. "We need to see the withdrawal of heavy weapons. This is what we are pushing for. And we need to see this happen now."

But European Council President Donald Tusk is among those who criticize the EU for "devoting all its efforts to make the Minsk II agreement work, even in the face of continued ruthless attacks on Debaltseve and other regions by the separatists militarily supported by Russia."

He said on February 20 that a point is quickly being reached when "further diplomatic efforts will be fruitless unless credibly backed up by further action."

Arkady Moshes, an analyst with the Finnish Institute of International Affairs and the program director of the EU's eastern neighborhood and Russia research program, says that Minsk II -- which he says was from the beginning worse for Ukraine than the original Minsk accord -- is "dead."

"I don't think that the EU has a backup plan," Moshes tells RFE/RL. "The EU's position is noble, in a way, because they are thinking of saving human lives and no one can criticize the EU for trying to do that. But the EU should realize that we are moving deeper into crisis and much more serious countermeasures will be required soon, I'm afraid."

In a speech to the European Parliament's Foreign Affairs Committee on February 24, Moshes urged the EU "to stop pretending, talking about things not as they are." He said Western leaders "have been too polite" and this weakens their effectiveness. He said the European Union should have "a list of preconditions that is set" and "that should be the end of the further conversations."

Already some in the EU, notably Tusk, are pushing for another round of sanctions against Russia. European Commission Vice President Vadis Dombrovskis said the commission is now considering additional sanctions that it could impose if Russia does not "start to play a constructive role in the conflict in eastern Ukraine."

And one major European leader who was not party to the Minsk talks, British Prime Minister David Cameron, is already upping the ante.

Cameron says his country will send 75 troops to Ukraine to train government forces battling pro-Russian separatists.

“Over the course of the next month, we are going to be deploying British service personnel to provide advice and a range of training -- from tactical intelligence, to logistics, to medical care, which is something else that they have asked for,” Cameron told lawmakers in London on February 24.

Cameron also left open the possibility of providing arms to Ukraine in the future and warned that failing to “stand up to Russia” would result in “instability” that “would be deeply damaging to all of us because you'll see further destabilization.”

European Parliament deputy Gabrielius Landsbergis is adamant that there should be no "third Minsk." He says that in addition to harsh, targeted sectoral sanctions, the EU should be preparing other measures.

"That is the weapon the EU has and that is the weapon the EU should employ," Landsbergis says.

The possibility of excluding Russia from the SWIFT international electronic-payments system should "be on the table," he adds.

He also believes the problem of securing Ukraine's borders "has been neglected" and that the EU or the Council of Europe could be the "main partners" in securing the border between Ukraine and Russia.

RFE/RL Ukrainian Service correspondent Zhanna Bezpiatchuk contributed to this report