Barack Obama will hold a formal meeting with Cuban President Raúl Castro at the annual United Nations general assembly in New York City on Tuesday.

This marks the second face-to-face meeting between the two presidents since the U.S. and Cuba restored diplomatic relations in 2014, The Guardian reported from The Associated Press. Earlier this month, Obama and Castro spoke via a telephone call before Pope Francis embarked visited their respective countries.

Aside from his meeting with Castro, Obama will convene with Kazakhstan President Nursultan Nazarbayev on Tuesday, The Guardian further reported. Obama also spoke with Chilean counterpart Michelle Bachelet over the weekend.

On Sunday's UN event, Russian foreign minister Sergei Lavrov called for the Obama administration to remove its embargo on Cuba and to terminate other permits which he said "bypassed the UN security council," The Guardian added. The U.S. and the European Union both enforced targeted sanctions on Russia for its occupation of Crimea and supporting rebel forces in eastern Ukraine.

Lavrov insisted that the decrees violates the UN Charter, and that it went against new global development goals and dented market principles in trade, finance, and technology, the news outlet noted.

Obama and Castro's first significant meeting took place in April, The Huffington Post reported. Obama described the meeting as "historic," adding that after the five-decade dispute between the U.S. and Cuba, "it was time for us to try something new, that it was important for us to engage more directly with the Cuban government and the Cuban people. And as a consequence, I think we are now in a position to move on a path towards the future, and leave behind some of the circumstances of the past that have made it so difficult, I think, for our countries to communicate."

Castro said that the two countries could have differences "with respect of the ideas of the others," The Huffington Post added.

"We could be persuaded of some things; of others, we might not be persuaded," Castro said at the time, as quoted by the news outlet. "Our countries have a long and complicated history, but we are willing to make progress in the way the president has described."

Barack Obama Calls for Getting Rid of Poverty

At the UN meeting on Sunday, Obama said that the world has progressed on reducing hunger, improving the treatment of disease, and taking people out of poverty, but challenges are still on the way, USA Today reported.

Though developmental programs are working, Obama said that the U.S. and other countries can strive harder to address issues such as bad governance, war damage, and gender, racial, and income inequality, USA Today listed.