Ukrainian Prime Minister Arseniy Yatsenyuk signed the political elements of a trade pact with the European Union on Friday, even as Russian lawmakers finalized annexation of Ukraine's Crimea region. The signing in Brussels signals Europe's solidarity with Ukraine -- and carries additional symbolic force because it was the decision by Ukrainian President Viktor Yanukovych in November to ditch the trade pact in favor of closer ties with Russia that triggered the protests that led to his ouster in February and spiraled into the current crisis. It also comes a day after the European Union and the United States slapped sanctions on Russian lawmakers and businessmen; Russia responded with its own list of sanctions against a number of U.S. lawmakers and officials.
@highlight
"Russia needs Europe more than Europe needs Russia," Cameron says
@highlight
Russia's President Vladimir Putin signs law allowing joining of Crimea to Russia
@highlight
EU leaders and Ukraine's PM sign the political part of a Ukraine-EU trade deal
@highlight
Tough U.S. and EU sanctions have been imposed on members of Putin's inner circle
Cameron said the measures agreed to in @placeholder will carry a cost for Crimea, whose goods would face heavy penalties and tariffs in Europe if they are shipped through Russia, not Ukraine.