"This is a process that is going to go on in the coming weeks," she said, when asked if Russia's response to Sunday's rebel ballot could trigger stiffer sanctions against Moscow.
The situation in Ukraine will be addressed at the next EU foreign ministers' meeting on Nov. 17, she said.
"I would say the main topic of discussion today should be ... how do we make sure that we find a solution to the conflict?" the former Italian foreign minister said.
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Mogherini said the "so-called elections" in eastern Ukraine were illegal and illegitimate and would not be recognized by the EU. There was a risk they could end chances for rebel dialogue with Kyiv and dialogue between Kyiv and Moscow, she said.