The European Union has identified defence cooperation as a key area for rebooting the crisis-hit bloc.
Led by France and Germany, the European Union has identified defence cooperation as a key area for rebooting the crisis-hit bloc after Britain's traumatic vote to leave.
"This is one of the fields where European Union integration is advancing the most," Mogherini said after EU defence ministers met in Malta.
Ministers would review progress in May and then it would be up to EU leaders meeting in June, or later in the year, to take "bold decisions if we want to deliver on defence and security," she said.
This could include efforts to relaunch a so-called rapid response force, which was approved as a rotating battle group led by member states a decade ago but never deployed, Mogherini told reporters.
"Now with crises all around, we hear from our partners, starting from the UN ... that a rapid reaction force from the EU would be needed to be deployed in some crisis areas," she said.
Mogherini has spearheaded efforts to give the EU the "hard power" to match its "soft power" influence.
Britain, nuclear armed and with a permanent veto at the United Nations, long opposed such efforts, fearing the creation of a "European army" commanded from Brussels.
But Brexit has taken Britain out of the equation and faced with doubts over US President Donald Trump's commitment to Europe's defence, Mogherini has led voices urging the EU to take on a more active defence role.
In March, defence and foreign ministers approved her plans for an embryonic military headquarters to coordinate EU overseas security operations.
German Defence Minister Ursula von der Leyen said it was "impressive to see that now all 27 member states (minus Britain) are ready to put the security and defence union on a good path."
"We see this year as the year of implementation."