The European Council meeting will get underway in Brussels on Thursday afternoon with the remaining 27 members of the bloc hearing Prime Minister Theresa May's reasons for asking for a delay in the UK's departure.
After the "usual exchange" with President of the European Parliament, Antonio Tajani, the group will "turn to Prime Minister May who will share her assessment of the latest developments regarding Brexit."
When May has left the room, the group will discuss the next steps concerning the UK's departure; especially in terms of the length of the extension, should May succeed in getting her vote through parliament next week to approve the Withdrawal Agreement, or not.
No final decision is expected from the EU leaders before the UK parliament votes again on the Brexit deal.
Chinese relations
In the evening, over dinner the 28 current EU leaders are expected to discuss a more defensive strategy for China, potentially signaling an end to the unfettered access Chinese business has enjoyed in Europe but which Beijing has failed to reciprocate.
European Commission Vice President Jyrki Katainen described the EU's economy as "fully open," while "China is not, and it raises lots of questions."
Chinese President Xi Jinping starts a tour of France and Italy this week. He has forecast a 'new era' in relations with Italy, expecting to sign an agreement in Rome for China's Belt and Road Initiative.
Economic and climate outlook
The agenda for the following day focuses on the economy: "The European Council will discuss the economic situation in the presence of President Draghi," Council President Donald Tusk wrote in his invitation letter to the leaders. "We will then address the future of our economic base, climate change, disinformation and the protection of elections and adopt the conclusions."
There had been hopes from climate activists that the EU heads of state would consider raising the bloc's climate objectives for 2030.
Five years ago, the EU committed to cutting its global warming emissions by 40 percent before 2030 but last week, the European Parliament voted to raise the objective to a 55 percent cut by 2030.
Tens of thousands of school children have skipped school to take part in organized rallies to protest climate inaction.