CAIRO/LONDON - Four Arab states refrained on Wednesday from slapping further sanctions on Qatar but voiced disappointment at its "negative" response to their demands and said their boycott of the tiny Gulf nation would continue.

Qatar earlier in the day accused Saudi Arabia, the United Arab Emirates, Bahrain, and Egypt of "clear aggression" and said the accusations cited when they severed ties a month ago "were clearly designed to create anti-Qatar sentiment in the West".

The four Arab nations accuse Qatar of supporting terrorism and allying with regional foe Iran, which Doha denies. Their foreign ministers met in Cairo on Wednesday after a deadline they gave Qatar to meet 13 demands expired.

They had been expected to consider further sanctions at the gathering, but announced no new measures.

"The response the four states got was overall negative and lacked any content. We find it did not provide a basis for Qatar to retreat from its policies," Egyptian Foreign Minister Sameh Shoukry said, reading out a joint statement after the meeting.

"The political and economic boycott will continue until Qatar changes its policies for the better," Saudi Foreign Minister Adel al-Jubeir told a news conference.

Qatar's response to the demands has not been made public.

Greater isolation

The UAE's minister of state for foreign affairs, Anwar Gargash, said in a tweet that Qatar faced "greater isolation, incremental measures and reputational damage" if it did not heed the demands.

Shoukry later told an Egyptian privately-owned broadcaster that the demands were non-negotiable.

"The matter from the beginning was not up for negotiations, ... there is no middle ground," he told the On television channel.

The worst inter-Arab rift for many years has aroused deep disquiet among Western allies who regard the region's ruling dynasties as essential partners in energy and defense.

The Arab countries have demanded Qatar curtail its support for the Muslim Brotherhood, shut down the Al-Jazeera satellite TV channel, close a Turkish military base and downgrade its relations with Iran.

Meanwhile, Germany said its intelligence service will participate in efforts to clear up accusations by Arab neighbors that Qatar supports terror groups.

German Foreign Minister Sigmar Gabriel visited Saudi Arabia, Qatar and mediator Kuwait this week.

He told Deutschlandfunk radio on Thursday there was an agreement for Qatar to "open all its books" to Germany's intelligence service "if we have questions about certain people or structures".

Reuters - Ap