The Saudi-led group boycotting Qatar has agreed to a 48-hour extension proposed by mediator Kuwait as part of efforts to resolve the row. The German foreign minister has meanwhile arrived in the Gulf region for talks.
As the deadline expired at midnight Sunday, Saudi Arabia, the United Arab Emirates (UAE), Bahrain and Egypt agreed to give Doha an extension to respond to their demands or face possible further sanctions.
One punishment reportedly being mulled is suspending Qatar from the six-nation Gulf Cooperation Council (GCC), a bloc allied with the US, according to Saudi-owned Al-Arabiya news channel.
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The GCC - made up of Saudi Arabia, the UAE, Bahrain, Qatar, Kuwait and Oman - could also extend trade penalties to include countries and companies dealing with Qatar, Al-Arabiya added.
Qatari Foreign Minister Sheikh Mohammed bin Abdulrahman Al Thani is set to give an official reply concerning the demands to Kuwait's ruling emir, Sheikh Sabah Al Ahmad Al Sabah, later on Monday, Al-Arabiya added.
The foreign ministers of Egypt, the UAE, Bahrain and Saudi Arabia will meet in Cairo on Wednesday to discuss "future steps" in dealing with Qatar.
On June 5, the four countries said they were severing diplomatic and travel ties with their Gulf neighbor, accusing it of supporting terrorism and being an ally of regional foe Iran, leading to the worst diplomatic crisis in the region in decades. Saudi Arabia has closed its airspace to Qatari carriers and blocked its only land border, a key route for food imports.
Last week, Qatar disclosed a list of 13 demands issued by the group, including downgrading ties with Iran, a regional rival of Saudi Arabia, ending support for Islamist groups and shutting down the Doha-based broadcaster Al-Jazeera and its channels. The United Arab Emirates has threatened Qatar with "divorce" from its Gulf neighbors if it failed to meet the demands, saying they were non-negotiable.
Later, the four countries placed on terrorism lists 59 people and 12 groups with alleged links to Qatar.
Germany calls for dialogue
German Foreign Minister Sigmar Gabriel, who on Monday arrived in Saudi Arabia at the start a tour of several Arab states, has called for a "serious dialogue" to end the crisis.
"For many weeks, the brotherly countries and neighbors of the Arabian peninsula have been locked in a conflict that has fueled concern," Gabriel said in a statement on Sunday.
"We are not on one side or the other," he said. "But this conflict is not only about those who are directly involved in it, it also affects us and our interests."
"We are convinced that the GCC must become a strong forum for cooperation and conflict resolution. We also strongly support the mediation efforts of the emir of Kuwait," he said, adding that Germany was calling for an end to the financing of terrorist organizations and extremists.
Gabriel is also to visit the United Arab Emirates, Qatar and mediator Kuwait on his three-day visit.
jbh/cmk (AFP, dpa)