Of the countries listed, Saudi Arabia is by far the biggest.
However, it is worth noting that you listed five countries, not six.
Seven of those countries are in the Arabian Peninsula: Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, United Arab Emirates and Yemen.
Iraq, Kuwait, Saudi Arabia, Bahrain, Qatar, Iran, U.A.E
Saudi Arabia, Yemen, Oman, Qatar, United Arab Emirates, and some count Kuwait as an Arabian peninsula country.
Saudi Arabia is a country with a medium population which is located in the continent of Asia. Countries near Saudi Arabia include Bahrain, Qatar, Kuwait and United Arab Emirates.
Saudi Arabia, Kuwait, Qatar, United Arab Emirates, Oman and Yemen
the names of the gulf countries are oman,yemen,u.a.e,Bahrain,qatar,Kuwait and Saudi Arabia
U.A.E.,Saudi Arabia, Qatar, Oman, Bahrain AND Kuwait.
Jordan, Iraq, Kuwait, Qatar, Oman and Yemen
U.A.E.,Saudi Arabia, Qatar, Oman, Bahrain AND Kuwait.
They are Oman, UAE, Saudi Arabia, Qatar, Bahrain, Kuwait, Iraq and Iran.
Top 10 Richest Country's in Middle East (1) Saudi Arabia (2) Qatar (3) United Arab Emirates (4) Kuwait (5) Egypt (6) Bahrain (7) Turkey (8) Cyprus (9) Israel (10) Oman
Turkish Arabian Peninsula: Bahrain Kuwait Oman Qatar Saudi Arabia United Arab Emirates Arabic Yemen so on...........................