WASHINGTON (AP) — The United States is welcoming a decision by European Union leaders to prepare tougher economic sanctions against Russia over its apparent invasion of Ukraine.

National Security Council spokeswoman Caitlin Hayden says the U.S. is working closely with the E.U. and other partners to hold Russia accountable for actions in Ukraine that the West deems illegal. Hayden says the E.U.’s decision shows strong support for Ukraine’s sovereignty and territorial integrity.

European Union leaders late Saturday asked their executive body to urgently prepare tougher economic sanctions that could be adopted within a week.

Russia’s aggressive behavior toward Ukraine will be a key agenda item at a NATO summit that President Barack Obama will attend next week in Wales.

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