U.S. President Barack Obama will arrive in Saudi Arabia Wednesday to attend the Gulf Cooperation Council summit. Three issues that are likely to dominate the talks between the American leader and members of the six-nation council — Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates — are the fight against the Islamic State group in Syria and Iraq, concerns of the mostly Sunni member states regarding the Iran nuclear deal struck last year and the ongoing proxy war in Yemen.

“It's going to be a tough visit,” Ilan Goldenberg from the Center for a New American Security, a Washington, D.C., think tank, told NPR. “If you want the Iranians and the Saudis to find a way to coexist, you first need to send a pretty strong signal to both of them. ... To the Saudis, that the U.S. will be there to have their back; to the Iranians, that there is a limit to what the United States will tolerate — and there will come a time if you act too aggressively, the United States will find a way to push back.”

The United States and Saudi Arabia, in particular, have long had a testy relationship. Washington has historically turned a blind eye to the kingdom’s abysmal human rights record, primarily due to geopolitical and economic concerns such as gaining foothold in the tumultuous Middle East and securing a steady supply of oil.

However, over the past year, this uneasy alliance has come under increasing strain, with many in the kingdom raising concerns that the U.S. does not share its regional interests — a suspicion hardened by Obama’s overtures to their longtime foe Iran. The nuclear deal between the Shiite nation and the P5+1 group of world powers finalized last year fuelled concerns that the U.S. is attempting to undermine traditional alliances in the region.

“The competition between the Saudis and the Iranians — which has helped to feed proxy wars and chaos in Syria and Iraq and Yemen — requires us to say to our friends as well as to the Iranians that they need to find an effective way to share the neighborhood and institute some sort of cold peace,” Obama recently said in an interview with the Atlantic magazine. “An approach that said to our friends ‘You are right, Iran is the source of all problems, and we will support you in dealing with Iran’ would essentially mean that as these sectarian conflicts continue to rage ... and would mean that we have to start coming in and using our military power to settle scores.”

Obama’s visit also comes at a time when Saudi Arabia — a country historically used to an oil-fuelled economic prosperity — is feeling the brunt of the precipitous drop in oil prices. Between September 2014 and February 2016, global oil prices dropped by about 70 percent, and the ensuing decline in oil-dominated export revenue led to Saudi Arabia’s budget deficit ballooning to $98 billion last year.

In December, the Saudi government announced a raft of spending cuts and reforms aimed at reducing the budget deficit to approximately $87 billion by the end of this year after the International Monetary Fund warned that the country may run out of cash in less than five years.

Obama’s visit is also aimed at prodding America’s Gulf allies to increase participation in Syria, where a protracted and multipronged civil war has pitched President Bashar Assad against rebel groups on one side, and militants of the Islamic State group, also known as ISIS or ISIL, on the other.

“There are many reasons why we feel it’s very important to de-escalate regional conflicts, first and foremost because of the devastating humanitarian impact that the conflicts in Syria and Yemen in particular have had,” Rob Malley, White House coordinator for Middle East policy, said during a press briefing last week. “The fight in Yemen has distracted from the crucial fight against ISIL and against al Qaeda. As that fight de-escalates, the countries that have been involved in that fight will be able to focus more of their activities against ISIL and against al Qaeda.”