Saudi Arabia, the United Arab Emirates, Bahrain and Egypt announced in the early hours of Monday they were pushing back a deadline for Qatar to agree to a list of 13 demands they issued on June 22.
A joint statement said they were extending the ultimatum, which had been due to expire at the end of the day on Sunday, at the request of Kuwait's emir.
Kuwait, which has been acting as a mediator in the crisis, has received assurances that "Doha would submit its official response to the demands to Kuwait on Monday," the statement said.
Doha said Qatari Foreign Minister Sheikh Mohammed bin Abdulrahman Al-Thani would deliver its response by hand to Kuwait's emir, Sheikh Sabah al-Ahmad Al-Sabah.
The demands include Doha ending support for the Muslim Brotherhood, closing broadcaster Al-Jazeera, downgrading diplomatic ties with Iran and shutting down a Turkish military base in the emirate.
Sheikh Mohammed had earlier said the list of demands was "made to be rejected".
Saudi Arabia and its allies announced on June 5 they were severing ties with their Gulf neighbour, sparking the worst diplomatic crisis to hit the region in decades.
They accused Doha of supporting extremism and of being too close to Saudi Arabia's regional arch rival Iran, which Qatar has strongly denied.
The crisis has raised concerns of growing instability in the region, home to some of the world's largest energy producers and several key Western allies hosting US military facilities.
German Foreign Minister Sigmar Gabriel, who on Monday starts a tour of several Gulf states, called for a "serious dialogue" to end the crisis.
"We are worried that the distrust and the disunity could weaken all the parties concerned as well as the entire peninsula," said Gabriel, who will visit Saudi Arabia, the United Arab Emirates and Qatar.
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They also ordered Qatari citizens to leave their territories and took various steps against Qatari companies and financial institutions.
It is unclear what further measures will be taken if Qatar fails to meet the demands, but the UAE's ambassador to Russia Omar Ghobash warned last week that further sanctions could be imposed.
As well as expelling Doha from the six member Gulf Cooperation Council, the Arab states could tell their economic partners to choose between doing business with them or with Qatar, he told Britain's Guardian newspaper.
Qatar has long pursued a more independent foreign policy than many of its neighbours, who tend to follow the lead of regional powerhouse Saudi Arabia.
Doha has said it is ready for talks to end the crisis. Kuwait, which unlike most of its GCC neighbours has not cut ties with Doha, has been heading up mediation efforts.
US Secretary of State Rex Tillerson has also called for compromise and hosted senior Gulf officials, but his efforts have been undermined by remarks from President Donald Trump apparently supporting Riyadh's position.
Trump spoke separately on Sunday with the Saudi king, Abu Dhabi's crown prince and the Qatari emir on his concerns over the dispute, the White House said.
Trump 'underscored that unity in the region is critical,' the statement said, but also 'reiterated the importance of stopping terrorist financing and discrediting extremist ideology.'
Cairo said that Egypt will host the foreign ministers of Saudi Arabia, the United Arab Emirates and Bahrain on Wednesday to discuss the crisis.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)