The increase in sentiment comes despite worsening geopolitical tensions, with Europe imposing sanctions on Russia following its incursion into Ukraine, and ongoing fighting in all of Gaza, Iraq and Libya.
There are also renewed fears about the region's banks, after the collapse of Portugal's largest bank by market cap and its subsequent $6.6 billion bailout by the government this week.
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Michele Raucci, an Italian financier and YPO member, told CNBC the bailout of Banco Espirito Santo was actually positive for Portugal's economy.
"The situation in Portugal is more of an issue for shareholders than for the economy itself. The economy does very well on this kind of restructuring, because the government is going to put more money into the economy," he said on Tuesday morning.
Notably, executives in Portugal, Greece, Italy and Spain are now more confident in their countries' prospects than those in economically stronger euro zone members.
"Less than two years after bailouts of Greece and Spain and the financial shock in Cyprus, the debt-laden euro zone periphery economies as a group became significantly more optimistic than the core economies for the first time in five years, a phenomenon that continued into the second quarter," said the YPO, following its survey of nearly 3,000 global CEOs in the first two weeks of July.