Iranian President Mahmoud Ahmadinejad is headed for the sunny beaches of Ipanema.

From June 20 to 22, Brazil's coastal city of Rio de Janeiro will host a UN Conference on Sustainable Development. More than 115 heads of state and government are expected to attend, including new French President Francois Hollande, Chinese President Hu Jintao and Russian President Vladimir Putin.  The U.S. will be represented by Secretary of State Hillary Clinton. 

That's quite a mixer, especially with Ahmadinejad on the guest list -- the Iranian leader has lately been the subject of increased economic sanctions and worsening diplomatic isolation.

No surprise, then, that many Brazilians want to take back their country's invitation. Agence France-Presse reports that hundreds of protesters, including many Jewish activists, gay Brazilians, and human rights advocates, marched along Rio's Ipanema beach on Sunday to criticize what they see as Ahmadinejad's religious intolerance.

At the rally, Jews blasted the Iranian president's denial of the Holocaust and threats against Israel. Gay couples protested the executions and jailing of homosexuals in Iran. Human rights activists deplored the oppression of Iranian youth movements.

This week's summit will address environmental protection and poverty, but the activists argued that these subjects were beyond Ahmadinejad's purview.

Brazilians' animosity is reflected even in the highest levels of government. Iran has been an economic partner to Brazil in recent years, but current President Dilma Rousseff, elected in 2011, is less inclined than her mentor and predecessor, Luiz Inacio Lula da Silva, to oblige Ahmadinejad.

In the 1970s, Rousseff endured three years in prison for her efforts to overthrow Brazil's military dictatorship. CNN reports that she was tortured, beaten and interrogated there. Now that she leads South America's largest country, she has little tolerance for human rights abuses.

So Ahmadinejad's record of oppression in Iran is off-putting, to say the least. His support for Syrian President Bashar al-Assad has deepened his divide from many Western powers, and his own successful efforts to suppress a youth-led rebellion following his disputed victory in 2009 elections were widely condemned. These days, suspicions of nuclear ambitions have made Iran a pariah state to much of the Western world, resulting in diplomatic isolation and harsh economic sanctions.

It is no secret that despite this isolation, Iran maintains strong alliances with Syria and Lebanon's Hezbollah, as well as economic partnerships with Russia, China, Turkey and others.

But Ahmadinejad's connections to countries in the Western Hemisphere are less discussed. His endeavors to strengthen those bonds signify Iran's awareness of the importance of the emerging economies there.

In January of this year, Ahmadinejad took a tour of Latin America countries in an effort to build those relationships. AP reports that while in Nicaragua, he called President Daniel Ortega his brother president. In Venezuela, a close diplomatic ally, President Hugo Chavez joked about the two leaders' shared enmity with the United States, laughing, When we devils get together... it's like they go crazy! The Iranian leader was also received in Ecuador and Cuba during the trip. Furthermore, there are signs of a growing relationship with Bolivia.

[Western powers] say we're making [a] bomb, said Ahmadinejad in January. Fortunately, the majority of Latin American countries are alert. Everyone knows that those words ... are a joke. It's something to laugh at.

It's uncertain whether these Latin American partnerships represent sustainable diplomatic progress for Iran. Sanctions imposed on the Islamic Republic may force Ahmadinejad to make economic allies where he can find them, but as appears to be the case in Brazil, those bonds can break.

Domestic human rights violations, allegations of rigged elections, and an ongoing evasion of nuclear inspections make Iran look like an unreliable ally in the long run. Despite more than a century of U.S. interference in Latin America, Washington is still a better diplomatic bet than Tehran for the region's democratically governed countries.

Rising and risen powers ... [including] Brazil will continue to flirt with Tehran, but when it comes crunch time, they know this is a core issue for the United States. And they're not going to jeopardize their most important relationship to please the Iranians, explained Karim Sadjadpour, an Iran expert at the Carnegie Endowment for International Peace, to the Washington Post.

In any case, long-term economic and diplomatic strategies were not the main concern of the protesters on Ipanema beach. For them, political and social repression were grounds enough for a protest against Ahmadinejad's very presence. And although the U.N. conference in Brazil will focus on environmental concerns, the Rio protesters argue that their criticisms are pertinent since human rights cannot realistically be divorced from those issues.

We want the world to know that religious hatred harms the environment and Ahmadinejad represents hatred, said Ivanir dos Santos, of Brazil's Commission Against Religious Intolerance, to AFP. Sustainable development encompasses human rights.