The lower house approved a law to reduce the number of MPs from 630 to 400 and senators from 315 to 200.

The reform was a flagship manifesto promise of the anti-establishment Five Star Movement (M5S), the main party in Italy’s ruling coalition.

The government says the cuts will streamline parliament and save hundreds of millions of euros in salaries and expenses.

In a post on Twitter, the M5S said the bill – which was supported by almost all parties – would save the country €1 billion over 10 years.

However, critics have warned that the cut could weaken democracy, and increase the influence of lobbyists over governing institutions – all for a minimal saving that will have little effect on debt-laden Italy’s book balance.

The new law should come into effect after the next elections, which are due in 2023.

The government’s other main objective is to pass a budget to block a rise in VAT (sales tax), which is set to kick in on 1 January if the government fails to reach its debt-reduction target.