Italy has voted to cut the size of the country’s parliament by more than a third, exit polls suggest.
More than 67% of people voted in favour of the change, according to a projection from state broadcaster RAI.
The number of MPs in the lower house will be reduced from 634 to 400. The senate will also be downsized.
The referendum was pushed by the Five Star Movement, part of the governing coalition, which argued that the move would reduce costs.
The move, which cuts the total number of MPs and senators from 945 to 600, had already been pushed through parliament.
But it needed to be backed by a referendum because it amends the constitution. The changes will have to be made before the 2023 election.
Foreign Minister Luigi Di Maio, a senior Five Star figure, described the result as “historic”.
“We can go back to having a normal parliament, with fewer privileges and 345 fewer seats,” he said.
Last October, Five Star said streamlining parliament will save the country €1bn (£918m) over 10 years.
However critics argue that the move will weaken democracy.
The referendum was held alongside a small number of regional elections.
Right-wing opposition leader Matteo Salvini said he was aiming for a clean sweep however his party appeared to make one gain – the eastern region of Marche. It stayed in charge of two other regions.
The centre-left Democratic Party held on to three regions it already rules including Tuscany.
The contest in Puglia was even, according to Ansa news agency.