The EU and the US have imposed travel bans and asset freezes against a number of Russian and Ukrainian officials.
The sanctions are targeting figures that are seen as having a key role in the March 16 referendum in which Crimea's population has voted in favour of seceding from Ukraine and joining Russia.
From economic point of view, there is no sense for Russia to annex Crimea, writes the German newspaper Die Welt.
The newspaper quotes Russia's finance minister Anton Siluanov who said that the annual deficit in Crimea's budget is around EUR 700 M and nearly half of it has been covered by Ukraine's state budget.
A new federal constitution and fresh elections are among suggestions that Russian Foreign Ministry made to Ukraine on Monday.
In a statement posted on its website, the Ministry of Foreign Affairs urged Ukraine's parliament to call a constitutional assembly and draft a new constitution which envisages handling more power to the regions.
"What's good for Serbia is good for Russia"
BELGRADE -- Russian Ambassador in Serbia Aleksandr Chepurin expressed the expectation that "the Serbian government would realize what Serbia needs most."
This is primarily in terms of economic development, he told Tanjug late on Sunday, commenting on the results of parliamentary elections.