Russia's Foreign Ministry has said that a declaration of independence approved by the pro-Moscow local
parliament in Crimea was "absolutely lawful".
The comment comes days ahead of a Sunday referendum on whether the region should become part of Russia.
"The Russian Foreign Ministry considers the decision of the parliament of Crimea absolutely lawful," the ministry said in a statement on its website on Tuesday.
Earlier in the day, the local assembly approved a "declaration on the independence of the autonomous republic of Crimea and the city of Sevastopol" with 78 out of 81 lawmakers present voting in favour.
The move by the parliament, which has been declared illegal by the new government in Kiev, appeared to be aimed at creating a legal framework for joining Russia as a sovereign state.
The parliament's press service said in a statement that independence would come into force after the referendum if the result is in favour of Crimea becoming part of the Russian Federation.
Western nations have said they will not recognise the referendum as legitimate.
If Crimea votes to join Russia it will be the first country to do so since the fall of the Soviet Union.
Speaking on Tuesday, Ukraine's ousted President Viktor Yanukovich accused his country's new government of creating a civil war and criticised the West for supporting it.
Speaking in the southern Russian city of Rostov-on-Don, Yanukovich repeated the Russian claim that the new Ukrainian authorities allowing far-right factions to take over the country, describing the new government as a "bandit regime" and said that their claim to power was illegitimate.
"I would like to ask those from the West, are you blind, have you forgotten fascism?" Yanukovich said. He also reiterated that he was still the legitimate leader of Ukraine and hoped to return.
"I remain not just the sole legitimate president of Ukraine but also commander-in-chief," he said, appealing to the armed forces to defy any "criminal orders" handed down by his foes.
Al Jazeera's Paul Brennan, reporting from Kiev, said that this was unlikely.
"The reality is that in Ukraine he is yesterday's man," he said.
Yanukovich told the new pro-West authorities in Ukraine who took over after he fled to Russia last month that "sooner or later, most likely sooner" they would be held responsible for their actions.
"You will be made responsible for the suffering of the people. Ukraine is now going through a difficult time," he said.
He blamed them for the fact that Ukraine appears about to lose control of Crimea.
"Your actions have led to the fact that Crimea is separating and the people of the south and east are demanding respect, even in the face of machine guns," he said.
The former president concluded his press conference by saying Ukraine needed to be united.
Meanwhile, Ukraine's acting president on Tuesday called for the formation of a national guard and for the mobilisation of reserves and volunteers into the country's armed forces to counter Russian military moves.