(CNN) US Secretary of State Rex Tillerson has extended his efforts to resolve a standoff between Qatar and four Arab nations, wrapping up a high-level meeting in Saudi Arabia with no sign of a breakthrough and announcing he will return to Qatar on Thursday.
Tillerson met in Jeddah with foreign ministers from the four nations leading the boycott of Qatar. Saudi Arabia, Bahrain, Egypt and the United Arab Emirates who accuse their gas-rich neighbor of supporting terrorism, a charge Doha denies.
In his efforts to find a solution, Tillerson spent Monday in Kuwait, which is helping to mediate the discussions, then flew to Qatar on Tuesday, before shuttling to Saudi Arabia on Wednesday. The State Department announced Wednesday that the top US diplomat will return to Doha on Thursday.
Tillerson left Jeddah without comment, but in brief remarks during the day, Crown Prince Mohammed bin Salman expressed appreciation for the US' efforts and for ongoing cooperation between their two countries.
"Especially at this time when there are many challenges, but also many opportunities," the prince told Tillerson. "But we both trust that the two leaderships in both countries we will be able to overcome all of these challenges."
Tillerson noted "the joint interests that we both share, our two countries, our mutual interest here in terms of security, stability for the region and economic prosperity for the region as well."
Tillerson went through a slew of meetings while in Jeddah, sitting down with the Saudi foreign minister, King Salman, the group of foreign ministers for a two-hour discussion, and the Crown Prince.
He will now return to Doha to meet with the Emir of Qatar and share the views he heard in Saudi Arabia, according to State Department spokesman R.C. Hammond.
The visit comes a day after Tillerson signed a memorandum of understanding between the US and Qatar on fighting terrorism. The top US diplomat said he hoped it might help facilitate progress on the dispute.
However, the four states responded with a joint statement saying the announcement of the memorandum was "not enough," and that sanctions on Qatar would continue until the "just and full demands that will ensure that terrorism is addressed and stability and security are established in the region."
The statement thanked the US for its "efforts" in the "fight against terrorism and its financing," saying the memorandum was the result of "repeated pressures and demands" from the four nations for Qatar "to stop its support for terrorism." Qatar denies that it funds or supports extremist groups.
Asked about the agreement as he greeted Tillerson at the airport, Saudi Foreign Minister Adel Al-Jubeir said: "We have many thoughts and I will discuss them with the Secretary."
A statement by Bahrain's Ministry of Foreign Affairs gave no indication that the Arab nations are looking for ways to ease up on Qatar.
The statement said the meeting discussed "ways to eliminate terrorism and all those who support or fund it." It went on to add that the ministers stressed "the need to intensify the efforts to eliminate this phenomenon and dry up its funding sources."
At its core, the dispute reflects long-standing Gulf frustration with Qatar's foreign policy, including its support for Islamist groups and its ties to Iran, with which Qatar shares the world's largest gas field.
The regional feud threatens to undermine a central foreign policy goal of the Trump administration, since all the countries involved in the dispute are members of the US-led coalition fighting ISIS. Qatar is home to the largest US military base in the Middle East, from which flights against the terrorist group are coordinated.
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The four countries have cut diplomatic ties with Qatar, closed their airspace to its airline, banned their citizens from traveling to or residing in Qatar after giving Qatari citizens 14 days to leave their countries after the decision was announced June 5.
Gulf officials have said the restrictions will stay in place until Qatar meets a series of demands, including severing all ties with Iran and "terrorist" groups, shutting down the Qatari media organization Al Jazeera, ending its military cooperation with Turkey and halting the construction of a Turkish military base on its territory, and aligning its foreign, military and political policies with its neighbors. Qatar has rejected those demands.
Additional Turkish troops arrived in Doha on Tuesday, the Qatari Ministry of Defense's moral guidance department said in a statement. This was the fifth group of troops to make it to Doha since June 19, shortly after the four Arab countries enforced their blockade on Qatar, it said.
"The defense cooperation between Ankara and Doha is part of the joint military cooperation vision to support counter terrorism and extremism efforts in the region and preserve security and stability," the ministry said.
Despite the mediation efforts, none of the parties have shown signs of backing down.
The United Arab Emirates said in a statement that Foreign Minister Anwar Gargash had sent a letter to Zeid Ra'ad Al Hussein, the UN High Commissioner for Human Rights, in which he argued that Al Jazeera's reporting "has repeatedly crossed the threshold of incitement to hostility, violence and discrimination."
Meanwhile, Egypt's Foreign Ministry told a meeting of the coalition against ISIS in Washington that Qatar should no longer be a part of the alliance. "It is no longer acceptable that the coalition partners include countries that support terrorism or promote it in its media," spokesman Ahmed Abu Zeid said.
Tillerson said Tuesday he was in the Gulf as a "friend to the region."
Speaking at a joint news conference in Doha with Qatari Foreign Minister Sheikh Mohammed al-Thani, the US Secretary of State said he was "hopeful we can make some progress to bring this to a point of resolution."
He added, "I think Qatar has been quite clear in its positions and I think very reasonable and we want to talk now (about) how do we take things forward, and that's my purpose in coming."
Work on the memorandum of understanding has been underway for as long as a year, Tillerson said. It lays out a series of steps the two countries will take over the coming months and years "to interrupt, disable terror financing flows and intensify counter terrorism activities globally," he said.
The agreement includes milestones to ensure both countries are accountable to their commitments. "Together, the US and Qatar will do more to track down funding sources, collaborate and share information and do more to keep the region and our homeland safe," Tillerson said.
He also applauded Qatar's emir for being "the first to respond to President Trump's challenge" at a May summit in Saudi Arabia to stop the funding of terrorism.
Qatari officials are pushing back against the boycott led by Saudi Arabia, Bahrain, the United Arab Emirates and Egypt. The four nations have been joined in their campaign by five others, including Yemen and the government based in eastern Libya.