Is a perfect storm brewing in euro zone?

Aris Messinis | AFP | Getty Images

Municipality employees shout slogans against the Greek Government in front of the Greek Parliament during a demonstration as Greek lawmakers prepared to vote late Wednesday on a controversial new austerity package involving a huge shake-up of the civil service with thousands of jobs on the line.

The euro zone crisis may have abated of late, but analysts have warned that growing political tensions in a number of euro zone countries could lead to a renewed bout of instability on the continent, right after Germany's elections in September.

"Everywhere you look in Europe you have politics that is very fraught indeed," Roger Nightingale, economist and strategist at RDN Associates told CNBC on Thursday.

Portugal's ruling coalition is teetering; in Spain, the Prime Minister has been tainted by a slush-fund scandal; in Italy, there have been disagreements in the ruling coalition overtaxes. But the most immediate source of tension is Greece, with reports the country needs new aid to tide it over.

(Read More: Greece faces September funding gap: Report)

On Thursday morning, Greece's parliament approved measures that would lead to thousands of public sector job cuts, a move required by foreign lenders including Germany, but one which has led to widespread protests.

"You now have the Greek people wanting one thing and the German people wanting another thing and a compromise which is going to make losers on both sides," Nightingale told CNBC's "Capital Connection."

Alastair Newton, political analyst at Nomura, warned those tensions could lead to a conflagration of the euro zone crisis in October, when the next review of Greece's bailout program is due.

(Read More: 'Uneasy Calm' in Euro Zone Bonds Could Be Over)

"Most of the risk is in government instability. If the Greek government fell and a party like SYRIZA (a left-wing anti-austerity party) came to power, then the scenario changes, as a Greek exit from the euro became a possibility again," Giada Giani, European economist at Citigroup told CNBC on Thursday.

For now, things are "artificially calm", Marchel Alexandrovich, senior European economist at Jefferies said. He added that he was most concerned about the risks of governments collapsing in Italy and Spain.

(Read More: Greece grinds to a halt as major public sector layoffs loom)

"That leaves a political vacuum and the activation of the [ECB's bond-buying program] becomes problematic.So there is this perceived safety net under the markets that may not actually work in the time of most stress," Alexandrovich said.

"We've got Portugal still in trouble, we've got Cyprus definitely needing more help before it goes downstream and there's the slush fund scandal in Spain, which has seriously weakened Rajoy," Newton said, noting that borrowing costs could soon rise on the back of these factors.

- By CNBC's Holly Ellyatt, follow her on Twitter @HollyEllyatt

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