Please see the following example, I think the ministers are quite specific, not all ministers, just those from the remaining 27 EU countries. So why there is no 'the' preceded?
If one were to include the article before ministers, it would change the meaning of the sentence:
The ministers from the remaining 27 EU countries have met in Brussels ahead of the deal being finalised on Sunday.
This would mean that either all ministers from those countries were present, or it may imply that there is only one minister per country. Since every country has a number of ministers, some of whom have nothing to do with the EU or Brexit, it makes no sense that all minsters from all those countries would meet. However, one country may send their minister of foreign affairs, where another country may send their prime minister, and some countries may send more than one minister.
Therefore
Ministers from the remaining 27 EU countries have met in Brussels ahead of the deal being finalised on Sunday.
Is an accurate description of what happened: a bunch of people met, and they all hold cabinet positions in one of the 27 remaining EU countries.
When we add "s" for plurals to some nouns without " the" , the meaning and impact of it may be changed to the other. For example: The people means men : whereas if we use peoples instead of the people , the meaning is changed as " countries "
