Johnson said: "It is very important to stress this was not an attempt to change the tide of the war in Syria or to have a regime change or to get rid of [Syrian President] Bashar al-Assad".
"I'm afraid the Syrian war will go on in its terrible, miserable way".
The bloc's lack of unity played out during the April 14 airstrikes as only two Member States took part in the attacks on Assad's chemical weapons facilities.
In a separate session, ministers discussed Iran's role in Syria's war, but there was no breakthrough on whether to adopt new sanctions proposed by Britain, France and Germany on Iranians accused of helping the Syrian regime.
But EU diplomats said there was no discussion yesterday to target Russian military figures who, along with Iran, have allowed Assad to regain rebel-held territory in Syria's seven-year war and who the West accuse of war crimes arising from aerial bombardments and gas attacks on civilians and hospitals.
However, EU diplomats cautioned that until European governments had more idea of what the United States was planning, it was not possible to quickly follow suit.
They called on all parties involved in the conflict in Syria to ensure humanitarian access throughout the country.
"Without Russia, it is impossible to resolve this conflict", insisted German Foreign Minister Heiko Maas on his arrival in Luxembourg, repeating his previous statements that Russia and the European Union need to continue being engaged in dialogue over the Syrian conflict.
Stef Blok, the Dutch Foreign Minister said: "We should keep on pushing for a solution through the UN Security Council".
Putin had previously warned against any "thoughtless and risky acts in Syria", which remains one of Moscow's closest worldwide allies and the key cog in the Kremlin's efforts to re-establish its influence in the Middle East.
German Foreign Minister, Heiko Maas, stressed that "this conflict can not be solved without Russian Federation, " adding that he wants a "constructive contribution" from the country. Most of its governments agree Assad can not continue as president for peace talks to succeed.