According to the newspaper, the letter was addressed to Representative Jerrold Nadler, as well as to other Democrats on Wednesday.
"Should Iran seek to dash toward a nuclear weapon, all of the options available to the United States — including the military option — will remain available through the life of the [nuclear] deal and beyond," Obama said in the letter, as quoted by the newspaper on Thursday.
Obama pledged to increase "missile defense funding for Israel, facilitate co-development of missile defense systems, and boost tunnel detection and mapping technologies." The president also vowed to boost cooperation with Israel and Persian Gulf countries to counter "Iran’s efforts to destabilize Yemen, its support for Hezbollah in Lebanon, and its efforts to preserve the government of President Bashar al-Assad in Syria."
On July 14, Iran and the P5+1 group of countries — Russia, China, France, the United Kingdom, the United States and Germany – announced a final comprehensive agreement on Tehran's nuclear program in exchange for sanctions' relief.
Under US law, members of Congress have until September 17 to fully review the final nuclear deal with Iran and approve or reject it.