The rouble has officially replaced the Ukrainian hryvnia as Crimea's currency, but both currencies will be accepted until January 2016
The rouble has become Crimea's official currency as Russia seizes complete control of the peninsula, but businesses are still dealing mainly in the Ukrainian hryvnia.
"From this day, we can officially make payments in roubles. The hryvnia remains in use until the first of January, 2016," Crimea's pro-Moscow prime minister Sergiy Aksyonov said on Twitter on Monday.
His deputy Rustam Temirgaliev, cited by Russia's RIA Novosti news agency, said pensions would be paid in roubles from Monday, and that 300 million roubles ($A9.1million) had been set aside for this.
Russia's official ITAR-TASS news agency said, in a report issued at midnight, that "today the rouble was officially put into circulation" in the Black Sea peninsula.
The law Russia's parliament adopted last week on annexing Crimea declares the rouble the territory's official currency, but that there would be a period of transition until January 1, 2016.
On the ground, however, banks and shops were still dealing almost exclusively in the Ukrainian hryvnia on Monday.
"We haven't received any instructions on the adoption of the rouble," said an official at a Sevastopol branch of Italian bank UniCredit.
An employee at Oschadbank concurred, saying: "We're not aware of anything. We haven't received a letter".
A staff member at a Post Office in Sevastopol said that pensions would be paid in roubles, "but we don't know when".
Store operators in Crimea's main port city also indicated they were still in the dark about the rouble's adoption.
"Our cash registers still haven't been configured for roubles, but tills at some large supermarkets are ready to take them," said a grocery store employee.
A municipality spokesman told AFP that the rouble had successfully entered into circulation.
"For the time being, prices will be denominated in two currencies, and can be paid in both," said Igor Dolgopolov.
One hotel said it was accepting payments in roubles but giving change in hryvnia.
The developments came as Ukraine ordered its outnumbered troops to withdraw from Crimea after Russia's seizure and annexation of the peninsula.