President Joe Biden has invited 40 nations to participate in the two-day virtual Leaders Summit on Climate, which will take place later this week. But three countries experts say are fueling the immigration crisis at the U.S. southern border aren’t on the list — even though those migrants are likely fleeing the effects of climate change. Invited countries include the 17 that make up the Major Economies Forum on Energy and Climate — a U.S.-led coalition created in 2009 meant to convene the world’s economic leaders in climate dialogue that includes China, Brazil and the European Union. These countries produce more than 80% of the world’s greenhouse gas emissions. Smaller nations such as Antigua and Barbuda, the Marshall Islands and Bhutan were invited not because of their impact on the earth, but the earth’s impact on them. As the planet warms, hurricanes, droughts and rising sea levels threaten these countries. But another group of nations, likewise reeling from the effects of climate change, won’t be attending. No country from Central America made the list, including El Salvador, Honduras and Guatemala. Destabilized by natural disasters and poverty, people are fleeing the turbulent “Northern Triangle” for America. “It’s a shame, because these issues are interconnected,” said Kayly Ober, senior advocate and program manager for the Climate Displacement Program at Refugees International. Ober said the absence might be a sign the Biden administration is looking to avoid derailing more direct conversations on immigration. Mr. Biden has put forth a $4 billion, four-year plan to address the root causes of Central American migration. However, Ober said, “to believe that [the Northern Triangle] shouldn’t be at the table and that they wouldn’t add nuance to climate action discussions is a little one-dimensional.” Mr. Biden has stated that the climate crisis fuels the immigration crisis. In a press conference last month, he blamed former President Donald Trump for not giving enough aid to the Northern Triangle in the wake of weather disasters. “When this hurricane occurred — two hurricanes [Eta and Iota] — instead of us going down and helping in a major way so that people would not have reason to want to leave in the first place because they didn’t have housing or water or sustenance, we did nothing,” said Biden. Vice President Kamala Harris has been appointed to lead the effort in addressing the root causes of the southern border crisis. At a White House immigration roundtable last week, Harris noted the link between climate change and Central American migration to the U.S. “We are looking at issues that relate to the need for economic development, a need for resilience around extreme climate,” she said. “These Northern Triangle countries — a large part of their economic base was agriculture, and then what the severe climate experiences have done in dampening and really harming their ability to have that economic driver in their countries.” Asked why not include these Central American countries in the summit, a White House spokesperson told CBS News that “the Summit is only one of several major climate-related events in the run-up to COP-26” and that the “primary objective of the Summit is to encourage the world’s major economies” to lead the climate fight. In addition to those big players, the White House spokesperson said the invited smaller countries “are especially vulnerable to climate impacts.” Rodolfo Contreras, cultural attaché at the Guatemala Embassy, told CBS News that climate-related discussions between the two countries are ongoing. “This is an issue that we have discussed bilaterally with the United States,” he said. “Possibly for this reason, no Central American country was invited to this particular Summit, however we foresee that it will be later discussed at the regional level.” El Salvador, Honduras and Guatemala were “absolutely” among the region’s most vulnerable to the effects of climate change — including severe weather events, droughts, and the devastating effects of unmitigated deforestation, said Cynthia Arnson, director of the Latin America Program for The Wilson Center think tank. Even so, Arnson was not surprised to see the Northern Triangle omitted. “Latin America and the Caribbean already, I think, have a disproportionate number of slots,” she said, noting that of the 40 invited nations, eight are from the Western Hemisphere, which is home to only 18% of the world’s population. Arnson told CBS News however that she was surprised not to see Costa Rica get an invite as the country “has been an environmental global leader for so many years, if not decades.” She also noted that the decision to invite Brazil’s controversial President Jair Bolsonaro has been scrutinized by climate activists on the ground. “I can only imagine that [the Biden administration] decided that given the scope of the problem in Brazil and the size of the country, that it made more sense to have them at the table than outside the room,” said Arnson. The Honduran and Salvadoran U.S. embassies did not respond to a CBS News request for comment.