Jean-Claude Juncker, the head of the EU’s executive, came under from MEPs on Wednesday.
But not from the European Parliament’s two largest political groups, the centre-right EPP and the Socialists; both back Juncker in a grand coalition deal.
But Eurosceptic and far-left parliamentarians hit out at his record on tax.
Malin Bjork, a Swedish MEP, wants a vote of no confidence to be passed.
“The European parliament is not a tribunal, we are a political body that gives confidence and can withdrawn confidence,” she told euronews.
“We have seen a politician that is for privatisation and social welfare cuts, and that bad enough and now on top of that we get a tax avoidance schemes onto the political agenda.”
Italy’s Five Star Movement also protested against Juncker. Their MEPs brandished placards during a vote in a European Parliament session.
The group’s leader, Beppe Grillo, turned up in Brussels to voice his disapproval at the recent revelations.
“Who elected him,” Grillo asked. “You now have a president of the commission who was a longtime finance minister of a tax haven.”
Juncker says the Commission is now working on a new draft law that would propose automatic exchange of information between EU member states.
