Juncker and Schulz in favour of eurobonds

"I am still in favour of eurobonds, but I had to take note that there will be no majorities for it in the foreseeable future," the centre-left's Schulz said.

He added that it would be already a great step forward if big projects could be funded with joint loans. The pilot phase of a so-called project bonds scheme was launched by the European Commission last year with €230 million worth of unused funds, boosted by loans from the European Investment Bank.

The first project funded under this scheme - an undersea gas storage facility in Spain - was however halted last year due to earthquakes detected in that area.

For his part, Juncker, who is from the same centre-right political family as German Chancellor Angela Merkel - the main opponent of eurobonds - said he had been in favour of the scheme for at least four years.

"In December 2010 I pleaded in favour of eurobonds together with the conservative Italian finance minister Giulio Tremonti," he said.

Juncker, who was the longest-serving Prime Minister in the EU until last year when he stepped down in a spying scandal in his home country Luxembourg, admitted the time has not yet come for eurobonds to materialise.

"But I think they are the right instrument in the long run," he said.

The two candidates were also in agreement one of them should take over the EU commission presidency after the May elections.

According to the Lisbon Treaty, the next EU commission president should be elected by member states and the European Parliament "taking into account" the result of the EU elections.

But Merkel has already poured cold water on expectations of any "automaticity", suggesting that she would favour the same old package deal where all EU top posts are awarded in backroom deals taking into account the political families, gender, old and new member states.

Both lead candidates disagree with this view.

"To make it clear: It will be one of us. If there is a majority in the Parliament for me, I will be commission president. If the majority is for Schulz, he will get the job," said Juncker.

Schulz also called on EU government chiefs to respect the vote. "If you say beforehand there is a top candidate and afterwards it doesn't count, it would be a highly problematic development in a democracy," he said.

"Heads of state and government cannot take decisions that elude reality. Who decides differently than Europe's voters, increases the gap between citizens and politics," Juncker added.

Too many hats?

Juncker did disagree with his rival on one point, however: the double-hatted function of Schulz as both President of the European Parliament and lead candidate for the Social Democrats.

"Every Parliament president who would be top candidate for the head of government in his country, would have to resign immediately as Parliament President," Juncker said.

Schulz defended the double-hatted job and said he is still doing the EU parliament presidency "beyond party politics" as his mandate requires him to.

"As a Prime Minister, Mr Juncker also carried out countless campaigns in his 19-year long reign," Schulz pointed out.

Schulz's Twitter account meanwhile has also sparked controversies - after he renamed the personal account where he has over 80,000 followers as Social Democratic candidate, while creating a new account for the European Parliament presidential activities - with only 2,800 followers so far.

In a letter addressed to Schulz, several entre-right, liberal, green and leftist MEPs express their "concern" about the change of his Twitter account.

They ask for his presidential activities not to be mixed with political campaigning, which would amount to a violation of the Parliament's code of conduct.