Spain has started working with European Union officials on a potential bailout, according to a report in the Financial Times today – but if it goes ahead, it will be a different beast to the three post-crisis bailouts already announced.

Spain’s sheer size means that its combined gross domestic product is bigger than all the previously bailed-out nations: Ireland, Portugal and Greece.

The source of its pain is also different to the sovereign debt problems of Greece. Spain’s ratio of debt to gross domestic product is lower than Germany's, and it has been narrowing its current account deficit. (Read More: Spain's 'Surreal' Situation)

The euro [EUR=X  1.3028    0.006  (+0.46%)   ] zone crisis itself is in a different phase, after the announcement of the European Central Bank(ECB)’s new bond-buying program, and Spain has made more progress along the reform route than many believe, according to Chris Watling, chief executive of Longview Economics.

“You wouldn’t have thought so from news-flow, but actually they’re quite advanced,” he told CNBC Europe’s “Squawk Box.”

The results of Spain’s financial sector review by auditor Oliver Wyman will be announced next Friday. The government is also preparing a new budget for 2013, to be announced next week, which the EU is believed to be helping shape ahead of a bailout announcement. Speculation about what both will contain has already increased.

“I think the crisis is largely contended with. The mechanisms are in place to solve it,” Watling said.

“They’re discussing a deal behind closed doors anyway and I think Spain would be mad not to put something in place,” he added.