The European Union has approved plans for a military headquarters to coordinate overseas security operations, foreign affairs head Federica Mogherini has said.
Ms Mogherini, who has pushed hard for the EU to take on an increased military role, said foreign and defence ministers of the 28 member states "unanimously" backed the project.
"Today we decided to establish a MPCC (Military Planning Conduct and Capability facility) which will command the EU's non-executive military missions," she told reporters.
The facility will initially run three operations - civil-military training missions in Mali, the Central African Republic and Somalia - which do not involve the use of force, other than in self-defence.
The EU has also mounted Operation Sophia in the central Mediterranean, which can use force to stop migrant smugglers, and Operation Atalanta, part of international antipiracy forces off the Horn of Africa.
These executive operations have their own command centres which will remain separate.
Ms Mogherini said the decision was a huge step forward for the EU after decades of division over what defence role the bloc should take on - with exit-bound Britain having long opposed it.
She spoke of a "certain pride" about the agreement.
"This is one of the fields where traditionally we have had in the history of the European Union more divisiveness - since the 50s we were struggling in the defence field," she said.
Britain's vote to leave the EU, stripping the bloc of one of its most powerful and nuclear-armed countries, plus doubts about US President Donald Trump's NATO commitment have given fresh impetus to efforts to step up military cooperation.
But top EU officials, including Ms Mogherini, have had to repeatedly issue reassurances that the bloc is not going to undercut NATO as the primary defence for Europe.
Besides Britain, many of the former Communist states of eastern Europe such as Poland and Hungary have argued consistently that NATO must come first, given the need for US support in facing a more assertive Russia.
"It is not a European army -I know this is the label going around - it is a more effective way of handling our military work," Ms Mogherini, a former Italian foreign minister, said as she went into the meeting earlier.
European Commission head Jean-Claude Juncker called for a common EU defence headquarters in September after the Brexit vote, resurrecting an idea that had circulated in the EU for years.
The new facility will initially have a small staff of around 30 and come under the EU's existing military structures.
Flanagan discusses migration with EU colleagues
Minister for Foreign Affairs Charlie Flanagan was in Brussels for the meeting of European Union foreign affairs ministers, with migration among the other topics discussed.
Security policy, Egypt, the Western Balkans and the Middle East was also on the agenda.
Mr Flanagan also held bilateral meetings with the foreign ministers of Denmark, Germany and Egypt.
The case of Dublin man Ibrahim Halawa, who is in jail in Egypt, was discussed during the meeting with Minister Sameh Shoukry.
"I emphasised my concern for Ibrahim’s health and welfare during his incarceration and the strong desire of the Irish government and the Irish Parliament to see Ibrahim returned to Ireland," Mr Flanagan said in a statement.
"Minister Shoukry once again reiterated the commitment of his government to resolve this case when a verdict is handed down by the court. He further undertook to look into the case up on his return to Egypt."