In Wednesday's concluding session at the Organization of Islamic Cooperation's Istanbul summit, leaders of Muslim countries declared East Jerusalem as the capital of the state of Palestine.
Today, the head of Palestinian Islamist movement Hamas called for fresh protests across the world against the US President's controversial recognition of Jerusalem as Israel's capital.
Riashi went on to say that the Lebanese government considered U.S. President Donald Trump's decision last week to recognize Jerusalem as Israel's capital "null and void".
He told the BBC: "He is declaring war in the Middle East, he is declaring war against 1.5 billion Muslims (and) hundreds of millions of Christians that are not going to accept the holy shrines to be totally under the hegemony of Israel".
In his speech, Egyptian Foreign Minister Sameh Shoukry said that Egypt deplored the unilateral American decision, saying it contravenes worldwide law.
"With this decision, Israel was rewarded for all the terrorist activities it has carried out". No actor, he added, has the right to violate the global law and historical rights by legitimizing the occupation of lands.
Jerusalem remains at the heart of the Israel-Palestine conflict, with Palestinians hoping that East Jerusalem - now occupied by Israel - might eventually serve as the capital of a Palestinian state.
The Muslim world and US allies in Europe have denounced the move, saying that it is detrimental to the ongoing peace process through which Palestinians hope to make East Jerusalem the capital of their potential state.
In response to Trump's decision, Abbas warned of diplomatic consequences, threatening to no longer make agreements with Israel.
Within an hour of the announcement, the Palestinian towns of Bethlehem, Jesus's traditional birthplace, and Ramallah in the Israeli-occupied West Bank briefly switched off their Christmas lights in protest.
Palestinian political factions in Gaza called for huge demonstrations on Friday to reject Trump's decision.