BRUSSELS — The coronavirus pandemic forced the European Union to postpone a scheduled summit for a week after EU Council President Charles Michel went into quarantine because a close collaborator was diagnosed with COVID-19. 

Spokesman Barend Leyts said Tuesday that Michel "today learned that a security officer, with whom he was in close contact early last week, tested positive for COVID." 

Leyts said that the European Council chief is "respecting Belgian rules" and "he has gone into quarantine as of today." 

Even as the United Nations held its annual General Assembly remotely with video screens, the 27-nation EU had been preparing to stage its second live summit in a little over two months. A July summit took place with exhaustive precautions and no reported health consequences. 

This week, it took one person from Michel's inner circle to test positive to scuttle plans two days ahead of the meeting. 

The summit set for Thursday and Friday was to address issues as wide-ranging as Brexit negotiations, climate change and the tensions between Greece and Turkey over energy rights. 

Preparations for the meeting were already in full swing when Michel made the sudden announcement. He postponed the summit by one week, to Oct. 1-2. 

Live summits with the leaders of EU nations coming to Brussels only resumed over the summer. Throughout the spring, they met through video conferences while staying in their own capitals. 

As the chief of the European Council, Michel is the host of the regular summits of EU leaders. In July, he forced the national leaders to stay for four days in Brussels to broker an 1.85 trillion-euro agreement on a pandemic recovery fund and long-term EU budget. 

The 27 leaders often wore facemasks and met in a room that normally holds 300 to accommodate social distancing. Key meetings were held on a roof terrace under the open sky. 

Tuesday's postponement is a setback to the EU leaders' hope for a return to normalcy. 

Michel, who tested negative for the virus on Monday, did not want to risk bringing the leaders together in one room, however big, for fear of further exposure. The decision to delay also took place against a background of irritation when government officials do not take the same care with precautionary measures as the general public does. 

Only last month, the EU's chief trade negotiator, Commissioner Phil Hogan, had to resign when he admitted flaunting some measures during a summer stay in his native Ireland. EU Brexit negotiator Michel Barnier tested positive for the virus in March. 

Almost 150,000 people in the European Union have died in the pandemic, which also has thrown the bloc into the worst economic crisis of its history.