"Nobody should exclude anyone," Lopez Obrador said at a public event.
The U.S. government has stated that Cuba, Nicaragua and Venezuelan President Nicolas Maduro's government were unlikely to be invited because the summit is meant to showcase democracy in the hemisphere.
Lopez Obrador in his remarks in Cuba's capital also said he would keep pushing for the United States to lift its decades-old embargo against Cuba.
Iraqi arrested in plot to kill ex-president Bush
An Iraqi man who sought political asylum in the United States plotted to kill former president George W. Bush, the Justice Department said Tuesday.
