Russian-installed officials in four occupied regions of Ukraine reported huge majorities of votes in favour of joining Russia as the United States planned a UN resolution condemning the referendums as shams and Moscow remained defiant.
* Europe is investigating what Germany, Denmark and Sweden said were attacks that caused major leaks into the Baltic Sea from two Russian gas pipelines at the centre of an energy standoff. It remains unclear who might be responsible.
* Final results of referendums in four occupied regions of Ukraine showed huge majorities in favour of joining Russia, Russian-installed officials said.
* The head of the upper house of the Russian parliament said that if the vote results were favourable it could consider the incorporation of the four regions on October 4, three days before Russian President Putin's 70th birthday.
* Ukraine will not be swayed by any nuclear threats from Moscow or annexation votes and will press ahead with its plan to wrest back all its occupied land from Russia, a Ukrainian presidential adviser said.
* Tuesday's nuclear warning by Dmitry Medvedev, deputy chairman of Russia's Security Council, is one of several issued by Putin and his associates in recent weeks.
* The United States will introduce a resolution at the United Nations Security Council condemning the referendums, the US Ambassador to the UN said.
* Three explosions were heard, then electricity cut out in Ukraine's second city of Kharkiv, a Reuters witness reported.
* The United States is preparing a new $US1.1 billion ($A1.7 billion) weapons package for Ukraine that will be announced soon, US officials said.
* The number of Russians entering the European Union has jumped after a partial military mobilisation ordered by Moscow, and illegal crossings are likely to increase should Russia decide to close the border for potential conscripts, EU border agency Frontex said.
Australian Associated Press
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