Arguably the most important economic development last year was the announcement of a new push toward a trade deal between the United States and the EU. Almost a year after President Barack Obama presented the initiative in his February 2013 State of the Union speech, negotiations over the Transatlantic Trade and Investment Partnership (TTIP) have made steady progress. But several challenges remain unaddressed while new ones loom on the horizon. As a result, it is uncertain whether a final agreement will be ready in time at the end of this year.

As the world’s largest trading and investment partners, representing three-quarters of global financial markets and almost half of world trade, any trade deal made between the U.S. and the EU would naturally be of enormous proportions. According to some official estimates, TTIP could add as much as $130 billion a year to the U.S. economy and 119 billion euros to the EU economy. The significance of this must not be underestimated. If the EU were to add two percent annual economic growth due to TTIP as some economists predict, this would be equal to adding a market the size of Argentina to the global economy every year.

Indeed, the creation of a single market for trade and services stretching from Hawaii to the Black Sea could stimulate the economies and create hundreds of thousands of new jobs in the U.S. and Europe – something that is desperately needed these days of slow growth and massive unemployment. TTIP could also help pave the way for smoother capital flows over the Atlantic, to the benefit of investors and entrepreneurs alike. Furthermore, TTIP is an opportunity for the U.S. and EU to align regulation that could reduce costs of business and investments while keeping high standards in place. If successfully agreed upon, TTIP may even serve as a model for the rest of the world and set the default global standards in production and trade.

Progress on the current negotiations has been made. In December, U.S. and EU officials completed their third round of TTIP negotiations. The fourth round is scheduled in March following a review session between U.S. and EU trade representatives. However, as negotiations now begin in earnest, more controversial issues will likely begin to surface, including divergent approaches to legislation, standards and regulations. Vested interests and looming protectionism on both sides of the Atlantic remain strong. There is also some fear in Europe that the trade deal would disproportionately favor American business interests at the expense of European ones.

As negotiations enter into the next phase, pressure from environmental groups, labor unions and consumer advocates will also increasingly be felt. Many of these groups have recently stepped up their criticism of TTIP. While this debate is of course essential, it also puts a heavier burden on proponents of the trade deal to explain TTIP’s potential benefits and debunk skeptics’ criticisms.

On top of this, the NSA scandal has already threatened to derail the TTIP negotiation process or at least divert attention away from it. Although EU officials claim that data protection and privacy issues lie outside the realm of the current trade negotiations, European outrage over the Edward Snowden revelations could still spill over into adversely affecting the TTIP negotiations. A final potential obstacle is the upcoming elections in both the EU and the United States this year. Both the election to the European Parliament in May and the midterm elections to the U.S. Congress in November could give populist groups like Europe’s anti-immigration parties and the Tea Party movement more of a say over trade policy.

In sum, 2014 will be a pivotal year for TTIP. Though the end of the year deadline for reaching a final agreement may ultimately prove too ambitious, this alone is not necessarily a reason for despair. On the contrary. Given what is at stake – a trade and investment deal of epic proportions with potential to drive economic growth and job creation on both sides of the Atlantic over the next decade – EU and U.S. leaders must use this year to push forward toward a deal that is as ambitious and as comprehensive as possible. They have no other choice but to do this – TTIP is a once in a lifetime opportunity that is simply too big to fail.