A source in Washington familiar with the discussions said a tentative deal had been reached by the parties and that it could be signed in a few weeks
Saudi Arabia's foreign minister said on Friday a resolution to a bitter dispute with Qatar seemed "within reach" after Kuwait announced progress towards ending a row that Washington says hampers a united Gulf front against Iran.
The United States and Kuwait have worked to end the dispute, during which Saudi Arabia, the United Arab Emirates, Bahrain, and Egypt have imposed a diplomatic, trade and travel embargo on Qatar since mid-2017.
US President Donald Trump's senior adviser Jared Kushner had held talks in Doha on Wednesday following a visit to Saudi Arabia.
"We have made significant progress in the last few days thanks to the continuing efforts of Kuwait but also thanks to strong support from President Trump," Saudi Foreign Minister Prince Faisal bin Farhan Al Saud told a Rome conference via videolink.
"We hope this progress can lead to a final agreement which looks within reach and I can say I am somewhat optimistic that we are close to finalizing an agreement between all the nations in the dispute."
A source in Washington familiar with the discussions said a tentative deal had been reached by the parties and that it could be signed in a few weeks.
"They're working towards taking what's an agreement in principle and getting it actually signed," the source told Reuters on condition of anonymity.
Kuwait's Emir Sheikh Nawaf al-Ahmad al-Sabah on Friday welcomed the developments, state-run news agency KUNA said.
It quoted him as saying "this agreement has shown that all concerned parties are keen on retaining the pan-Gulf and the pan-Arab solidarity, unity, and stability."
US Secretary of State Mike Pompeo, speaking remotely at a Bahrain summit on Friday, said the United States was "very hopeful" that the dispute would be resolved.
All countries involved are US allies. Qatar hosts the region's largest US military base, Bahrain is home to the US Navy's Fifth Fleet, and Saudi Arabia and the UAE host US troops.
Washington has been pushing for reopening Gulf airspace for Qatari aircraft as a first step, diplomats and sources have said.
The boycotting nations accuse Doha of supporting terrorism. Qatar denies the charges and says the embargo aims to undermine its sovereignty.
'An imperative step'
Kuwait's Foreign Minister, Sheikh Ahmad Nasser al-Sabah, said earlier on Friday that fruitful discussion had taken place recently "in which all sides expressed their keenness for Gulf and Arab unity and stability, and to reach a final agreement that realises lasting solidarity".
In a Twitter post, Qatar's Foreign Minister, Sheikh Mohammed bin Abdulrahman Al-Thani, welcomed the Kuwaiti statement as "an imperative step" towards resolving the rift.
United Nations Secretary General Antonio Guterres is encouraged by the Kuwait statement and hopes all countries involved work together to formally resolve their differences, UN spokesman Stephane Dujarric said.
Iran's Foreign Minister Mohammad Javad Zarif in a Twitter post said he hoped Gulf reconciliation "contributes to stability and political and economic development for all peoples of our region."
The Qatari minister earlier told the Rome conference that Doha hoped "things will move in the right direction" but that any resolution should be based on mutual respect for sovereignty, including in foreign policy.
Doha had been set 13 demands, ranging from closing Al Jazeera television and shuttering a Turkish base to cutting links to the Muslim Brotherhood and downgrading ties with Iran, which shares a significant gas field with Qatar.