EU finance ministers meeting in Helsinki discussed a possible update to the EU's rules on public spending, but key countries Germany, France and the Netherlands were represented by subordinates.

Italian Prime Minister Giuseppe Conte called this week for the EU's Stability and Growth Pact, which limits budget deficits to three percent of gross domestic product in member states, to be "improved" and simplified.

The pact was the main bone of contention between the European Commission and the previous populist government in heavily indebted Italy, which must submit a balanced budget to Brussels in the coming weeks.

Reforming the rules, which also include a 60 percent of GDP cap on debt, sharply splits Italy from the EU's richer members that are loathe to ease the pressure on Rome's chronic overspending.

French Finance Minister Bruno Le Maire said any attempt to modify the rules would be too contentious and the EU must prioritise other challenges, especially investment.

"I am very cautious on ideas to change the rules," Le Maire said in Helsinki on Friday before jetting off early from the two-day meeting.

A reform would be "very difficult, very long, and very uncertain," added Le Maire, who was seen as a potential ally for Rome in the debate.

Officials said the long-planned discussion on Saturday very generally explored ways to simplify the rules and new ways to measure national spending.

Northern countries, led by the Netherlands, accuse the European Commission of loosely interpreting data in order to give deficit-running countries leeway. The current system has helped absolve countries such as Spain, Belgium and France, critics allege.

EU commission vice president Valdis Dombrovkis said an overhaul would only take place if an agreement seemed possible.

"We should avoid the scenario where we just open legislation without knowing how we'll close it and then have a long and divisive debate on this and not achieve results," he said.

Italy's new finance minister Roberto Gualtieri downplayed the significance of his absent counterparts, which also included Spain's finance minister.

"We are in a preliminary phase of reflection... It was an informal discussion," Gualtieri told reporters.