The conservative Merz returned to Berlin appearing less than impressed with the hot and humid Amazonian city, which became the unlikely stage for UN climate talks this year.

"We live in one of the most beautiful countries in the world. I asked journalists who accompanied me to Brazil last week: 'Who among you would want to stay here?' No one raised their hand," Merz said after returning from a leaders summit in Belem.

"Everyone was delighted to be back in Germany and to have left that place."

In the run up to COP30, Lula brushed off concerns about Belem's limited infrastructure and dire shortage of hotel rooms as he sought to put the world's largest tropical rainforest at the center of the talks.

Responding to Merz's comments, Lula said he should have gone to a boteco -- a relaxed Brazilian bar where snacks are served -- in Belem, which is located in the state of Para.

"He should have gone dancing in Para. He should have tasted Para's cuisine. Because he would have realized that Berlin doesn't offer him ten percent of the quality that the state of Para offers."

Merz's comments also angered local authorities and some Brazilians on social media jokingly compared it to Germany's infamous humiliation of Brazil at the 2014 World Cup -- when the national team lost by seven goals to one.

Helder Barbalho, the governor of Para, slammed Merz's comments as "prejudiced."

"It's curious to see that those who have contributed to global warming are surprised by the heat in the Amazon," he said in a post on X.

"Unfortunately, the German chancellor delivered a speech full of arrogance and prejudice, unlike his people, who are showing their fascination for our city in the streets of Belem," city Mayor Igor Normando said on X.

On the UOL news site, a column by journalist Jamil Chade, published on Tuesday, was titled: "Merz, your xenophobia is the new Berlin Wall."

On a Brazil forum on Reddit, one user who said he was from Para state, said Merz's comments still didn't hurt as much as the now-mythic football match.

Following the controversy, Merz's office sought to smooth things over.

In a statement to AFP on Tuesday, his spokesman said "the Chancellor expressed his regret that time constraints prevented him from better experiencing the impressive natural beauty of the Amazon region."

He also conveyed his "great respect for the achievement of having been able to organize such an important international conference in Belem."

Earlier on Monday, in a speech during a plenary session of COP30, German Environment Minister Carsten Schneider praised the "wonderful people of Brazil" who "captivated him with their warm hospitality."