The move comes as war continues to rage in Ukraine following Russia’s invasion in February.
Speaking to reporters, Mr Martin also raised fears over the prospect of famines in parts of the world due to Russian blockades on Ukrainian grain leaving the country.
The council meeting saw EU candidate status granted to both Ukraine and Moldova.
Georgia’s bid to become a member state was also acknowledged, with the country formally offered a “European perspective” – a step below candidate status.
“This is a very significant European Council meeting,” said Mr Martin.
“It’s historic in the sense of the enlargement of the European Union and I’m particularly pleased as a long-standing advocate for Ukraine’s application to candidate status to become a member of the European Union.
“It’s very significant for Ukraine, very significant for Moldova and, indeed, Georgia, in terms of European perspective.
“We in Ireland know what the European Union means, being a member of the European Union. It’s the 50th anniversary of Ireland’s decision to join the European Union, probably the single most transformative decision and event that happened in modern Irish history.
“So, I always cannot comprehend how we could ever refuse accession to other member states, because we know that membership itself can be transformative.
“It can spur on reforms, can spur on economic development, and notwithstanding that Ukraine is going through a terrible, terrible, inhumane war, their cities and towns have been levelled, their people have been terrorised – the greatest humanitarian crisis since World War Two.
“And I think today the European Union is sending a message of solidarity to the people of Ukraine that you belong to the European family, you belong to the European Union, and the decision will be taken today to facilitate your application and you will have candidate status to join the European Union along with Moldova and, over time, with Georgia.”
On the issue of blockades on Ukrainian grain exports, Mr Martin accused Russian president Vladimir Putin of “weaponising” hunger.
“There (are) no sanctions against the movement of food and Europe has been very clear about that because we do not want to, in any shape or form, be a catalyst for any famine or hunger and that’s the big fear at the moment because of the fact that grain is not getting out of Ukraine, that there could be very significant impacts in terms of famine and that’s a big worry, particularly around the Horn of Africa, the Middle East and so on,” he said.
Asked to comment on claims that Irish imports of some Russian goods have actually increased, Mr Martin added: “All the safeguards have been taken. We’re very alert to our role as a country to make sure that the sanctions are enforced and are adhered to and we’ll be taking every precaution (at the) ports and general surveillance to prevent that from happening.
“But on food and materials that give rise to the production of food, we’re very clear – there are no sanctions in relation to that because people need food around the world.
“Putin has weaponised food, he’s weaponised energy, he’s weaponised migration as part of his overall war effort, which I think is wholly immoral and wrong.”