Taoiseach Leo Varadkar is to travel to Brussels on Thursday for a meeting of EU leaders where the Windsor Framework will be discussed.
The leaders of 27 EU countries are also expected to discuss economic issues, energy and migration, and will meet the UN secretary general Antonio Guterres.
It comes after EU member states approved the framework on Tuesday, and after a key element of the EU-UK agreement – the Stormont brake – was endorsed by 515 votes to 29 in the House of Commons on Wednesday.
The DUP voted against it, with party leader Sir Jeffrey Donaldson saying they wanted assurances that EU law could not impede Northern Ireland’s ability to trade with the rest of the UK.
Speaking ahead of the European Council meeting, the Taoiseach said the latest developments on the Windsor Framework and the “difficult situation” in Ukraine would be discussed.
“I am joining other EU leaders in Brussels to reaffirm our solidarity and continued political, economic, military, financial and humanitarian support to Ukraine.
“As we have said before, we will stand with Ukraine for as long as it takes.
“We will discuss recent developments regarding the Windsor Framework and there will be an important discussion on economic issues, including how to ensure Europe’s future prosperity.
“I will be encouraging further work to improve the competitiveness of the European economy, making the most out of our single market, to drive future growth.
“We need to accelerate the green transition, boost skills, strengthen the single market and maintain an open and ambitious trade policy.”
European Commission vice-president Maros Sefcovic is due to travel to London on Friday, where he is to meet with Foreign Secretary James Cleverly and Northern Ireland Secretary Chris Heaton-Harris as part of the EU-UK Joint Committee.
This was a body set up as part of the Brexit process to oversee the implementation of the protocol and facilitate any changes as may have been required.