In a letter posted on the presidential website, Rouhani warned Muslim leaders gathering in Saudi Arabia’s Mecca they should not be distracted by Washington’s "divisive measures."
"The ominous conspiracy of Deal of the Century is after destruction of the Palestinian cause and promoting occupation aggression against all Islamic countries", he wrote.
Saudi Arabia has been hosting three emergency summits of Gulf Arab leaders in Mecca, attempting to address the escalation of US-Iran tensions in the Middle East.
US President Donald Trump said at the start of his term he would present his roadmap for ending the decades-old row between Israel and Palestinians, who seek to create their own state with the capital in Jerusalem.
The economic part of the US plan is expected to be unveiled at a workshop in Bahrain in late June. It will reportedly encourage wealthy Arab states to pay for Palestinian projects but suggest that Israel keep the occupied Palestinian lands.
Commenting on the issue on Friday, the leader of the Palestinian Authority, Mahmoud Abbas, said that Palestinians reject the "prosperity instead of peace" plan for the solution of the conflict with Israel.