The EU imposed additional sanctions Thursday on Crimea, banning all investment and cruise ships from its ports to force home the message the bloc will not recognise Russia's "illegal annexation" of Ukraine territory.
"The annexation is illegal and what we are doing is part of the non-recognition" policy, European Commission spokeswoman Maja Kocijancic said, calling on Russia to help end the Ukraine crisis which has cost more than 4,600 lives since Moscow seized Crimea in March.
EU foreign ministers agreed last month to take further action over Crimea, with the latest measures approved by the 28 members grouped in the European Council, its political arm.
Under the new restrictions, European Union companies will not be allowed to buy real estate in Crimea, finance local companies or supply related services.
Tourism services are also banned, with cruise ships barred from Crimea ports, except in an emergency.
EU companies can no longer export goods or technology for use in the transport, telecoms and energy sectors, specifically for gas and oil exploration and production.
In June, the EU halted imports from Crimea as part of wider sanctions including asset freezes and visa bans against Russian and Ukraine individuals and firms held responsible for driving the crisis.
After the July shooting down of a Malaysia Airlines jet over eastern Ukraine, blamed on pro-Moscow rebels using a Russian-made missile, Brussels extended the sanctions to key economic sectors such as finance, energy and defence.
But many EU member states were reluctant to take that step and diplomats say there is little appetite now to go much further.
Against that backdrop and with the West ruling out military force, there has been some concern that Russia's annexation of Crimea is fast becoming a fait accompli which would not be challenged.
Russian President Vladimir Putin insists Crimea is sacred territory which Moscow will never give up.
EU leaders are due to review overall ties with Russia at a summit Thursday and Friday which, according to a draft communique, will restate their position that further sanctions depend on the situation on the ground.