The source, who spoke to reporters on condition of anonymity, detailed the five principles as follows:
A full implementation of the Minsk ceasefire agreement in eastern Ukraine as a condition for any changes in EU policy toward Russia; bolstering EU ties with its eastern partners; strengthening the EU’s resilience; maintaining exclusively EU interests in any kind of engagement with Russia; engaging in people-to-people contact and supporting civil society in Russia.
The source added that all top diplomats had voiced support for the principles listed by Mogherini.
The bloc and its allies have imposed several rounds of sanctions on Russia, accusing it of playing an active role in the conflict between government forces and militias in eastern Ukraine. Moscow has roundly rejected the allegations, arguing that it has played no role in the crisis.
The Minsk ceasefire deal, worked out by Russia, Germany, France and Ukraine in February 2015 was due to expire at the end of last year but was extended into 2016.