An emergency meeting of Arab and Islamic states is taking place in Qatar in response to Israel's air strike on Hamas leaders in Doha last week.
A draft resolution seen by the Reuters news agency condemns what it calls Israel's hostile acts including genocide, ethnic cleansing, [and] starvation, which it says threatens prospects of peace and coexistence. Israel has strongly denied such allegations.
It is not clear what practical decisions could be taken, as analysts say any kind of military response is out of the question.
Earlier, Qatari Prime Minister Mohammed bin Abdulrahman bin Jassim al-Thani urged the international community to stop applying double standards and to punish Israel.
On Sunday, US President Donald Trump stated that Qatar has been a very great ally. Israel and everybody else, we have to be careful. When we attack people we have to be careful.
During his visit, Rubio will meet Israeli leaders to discuss the war in the Gaza Strip and other key issues affecting the Middle East.
The Israeli strike on Qatar's capital was last week condemned by the UN Security Council.
Israel defended its action, with President Isaac Herzog asserting it was necessary to remove some of the people if they are not willing to get a deal to end the war.
Hamas stated that its negotiating team survived the Israeli strike but lost five members, including the son of a key negotiator. A Qatari security officer was also killed.
Qatar has played a crucial role in diplomatic efforts to end the conflict, hosting Hamas's political bureau since 2012 and serving as a mediator between Hamas and Israel.
