The 85-year-old said Russian troops were meant to replace the government with “decent people” then leave.
The three-time Italian PM is a long-term ally of the Russian president.
This weekend his party is expected to take power as part of a right-wing coalition in a general election in Italy.
A narrative alleging the Ukrainian government was slaughtering Russian speakers in the east of the country was created by the media in Moscow, Mr Berlusconi told Italian TV.
He said the reporting, pushed by separatist forces and nationalist politicians in the Russian government, had left Mr Putin with no choice but to launch a limited invasion.
“Putin was pushed by the Russian population, by his party and by his ministers to invent this special operation,” he said.
“The troops were supposed to enter, reach Kyiv in a week, replace the Zelensky government with decent people and a week later come back,” Mr Berlusconi added.
“Instead they found an unexpected resistance, which was then fed by arms of all kinds from the West.”