BRUSSELS (AP) — German Chancellor Angela Merkel says Europe is “on thin ice” in its battle against the coronavirus, as the highly contagious delta variant threatens to undo progress made in reducing infections. A stronger response to the pandemic was a main topic of discussion among European Union leaders on Thursday at a meeting in Brussels, where they agreed that vaccinations should be sped up even more. In what might have been her last government declaration to the German parliament, Merkel noted that the number of COVID-19 cases in the 27-nation bloc continue to decline, while vaccination rates climb. But she told lawmakers: “We need to remain vigilant.”