Saudi Arabia, the UAE, Bahrain and Egypt released a joint statement naming 9 charity organisations and 9 individuals "directly or indirectly linked to Qatari authorities" as "terrorist"
Saudi Arabia and its allies unveiled a "terrorist" blacklist on Tuesday of 18 organisations and individuals suspected of links with Islamist extremism that they said had ties with regional rival Qatar.
The move by the four Arab governments came despite mounting international pressure to compromise in their weeks-old boycott of their fellow US ally.
Saudi Arabia, the UAE, Bahrain and Egypt blacklisted nine charity and media organisations and nine individuals "directly or indirectly linked to Qatari authorities" as "terrorist", a joint statement carried by the Saudi Press Agency said.
"We expect Qatari authorities to take the next step and prosecute the terrorist groups and people," the statement added.
The four governments have been boycotting Qatar since June 5 in the region's worst diplomatic crisis in years.
US Secretary of State Rex Tillerson, who last week spent four days in the region trying to broker a settlement of the crisis, has voiced satisfaction with Qatar's efforts to address any suspicion of terror funding.
The four governments on Tuesday blacklisted three organisations based in Yemen and six based in Libya accusing them of ties to Al-Qaeda.
They also blacklisted three Qataris, three Yemenis, two Libyans and a Kuwaiti they said were implicated in "fundraising campaigns to support (former Al-Qaeda affilate) Al-Nusra Front and other terrorist militias in Syria".