The fresh vote was called for January 25 after Greek lawmakers failed three times to elect a successor to 85-year-old President Karolos Papoulias, whose five-year term ends in March.
Equity markets fell across Europe and the United States amid market fears that an election victory for the anti-austerity far-left Syriza party could roll back measures set by the "troika" -- the European Commission, European Central Bank and IMF -- under the terms of Greece's bailout.
"Greece must stick to its commitments not only because the troika imposes them but also because it is good for the future of the Greek economy," Spanish Economy Minister Luis de Guindos told radio Cope.
He recalled that Greece benefited from the solidarity of European nations, including Spain, when it received a bailout in 2010 and 2012.
"Greece received 210 billion euros from the eurozone, including €26 billion for example from Spain" which was also in crisis and needed a eurozone bailout for its banks, the minister added.
"It is a demonstration of solidarity. Thanks to this financing, which Greece could not get from financial markets, it was able to maintain all of its public services," he added.
Greece was able "to pay its doctors, its police, its retirees, thanks to this solidarity," he added.
"This is a factor to take into account and I think the Greek population, when they vote on January 25th, will take it into account," de Guindos added in an interview with radio Onda Cero.
Syriza had dismissed warnings that its electoral programme could shake the markets but, within hours of the election being called on Monday, the International Monetary Fund said it was suspending further bailout payments to Greece until a new government was formed.
The anti-austerity party, which declined to vote in the presidential ballot in order to force snap legislative polls, wants to raise salaries and pensions, halt layoffs and freeze the privatisation of state assets -- key elements of reforms demanded by Greece's EU-IMF creditors.
If Syriza were to win it would still need to form a coalition and tone down some of its rhetoric to find a partner, analysts said.