The decision came after Saudi Crown Prince Mohammed bin Salman held a surprise meeting with a Qatari royal family member whose branch of the family was ousted in a palace coup in 1972.
Saudi state media broke the news overnight. Qatar did not officially comment on the deal until its foreign minister was pressed on Thursday by reporters during a briefing in Sweden, some 12 hours later.
Foreign Minister Sheikh Mohammed bin Abdulrahman Al Thani said he welcomed the Saudi decision, but that the measures must also include a full lifting of the blockade.
The way in which the deal was reached and announced out of Saudi Arabia raised questions about the level of the Qatari government's involvement. Qatari officials did not immediately respond to an Associated Press request for comment.
The official Saudi Press Agency reported that Qatari pilgrims will be allowed to enter the kingdom by land and would then be flown onward from two Saudi airports in Dammam and al-Ahsa at the king's expense. The king also ordered that aircraft from the country's flagship carrier be dispatched to Qatar's capital, Doha, to fly Qatari pilgrims to the Red Sea city of Jiddah — nearest to Mecca — and to host them at his expense for the hajj.
Saudi state TV said 100 Qataris had arrived at the border crossing on Thursday.
The decision came after Prince Mohammed met with Qatari royal family member Sheikh Abdullah Al Thani late Wednesday at a palace in Jiddah. Images broadcast on Saudi media showed the two men seated and smiling for cameras.
Sheikh Abdullah, who's lived previously for some years in Saudi Arabia and has gone back on private visits, has no role in government and his last position was as head of the equestrian and camel racing federation in the 1970s and 1980s, said Gerd Nonneman, a professor of International Relations and Gulf Studies at Georgetown University in Qatar.
Sheikh Abdullah's grandfather, father and brother were rulers of Qatar until a palace coup ousted his branch of the royal family in 1972.
"He's certainly not an envoy of the Qatari government. This was not a deal that was struck," Nonneman said, describing it as a Saudi "propaganda ploy" to catch the Qatari government off-guard.
He said Saudi outreach to various individuals within Qatar's large royal family causes discomfort and "needles the Qatari leadership."
Sheikh Abdullah was quoted as telling the Saudi prince that the ties between the two countries "are brotherly relations rooted in history." Saudi Arabia's crown prince responded in kind, emphasizing the historical ties between the two royal families, according to the Saudi Press Agency.
The meeting in Jiddah was the first by a Qatari royal in Saudi Arabia since a political standoff erupted 10 weeks ago when the kingdom, the United Arab Emirates, Bahrain and Egypt severed ties with Qatar. The quartet also halted direct flights, expelled Qatari residents and the three Gulf countries ordered their citizens in Qatar to leave. Saudi Arabia sealed Qatar's only land border.
Mixed-nationality families in the Gulf were affected by the measures, and Qatari students in the Gulf countries were pulled out of final exams. The crisis has also strained traditional kinships in the region.
Qatar's National Human Rights Committee issued a brief statement Thursday responding to what it said were "reports in Saudi media" outlining the kingdom's measures for Qatari pilgrims.
The committee expressed its "satisfaction" with the decisions, but reiterated its demands that the hajj not be politicized and said the Saudi measures remain "unclear," particularly regarding the facilitation of hajj for foreigners residing in Qatar. The statement noted that the agreement does not include allowing Qatar Airways flights carrying pilgrims.
The statement also called "for further measures to lift the siege entirely on citizens and residents of Qatar."
Hundreds of thousands of pilgrims from around the world have already arrived in Saudi Arabia for the hajj, which begins late next week. Saudi Arabia prides itself on hosting millions of pilgrims annually at Islam's holiest sites in Mecca and Medina.
Qatar's human rights committee had previously filed a complaint with the U.N. special rapporteur on freedom of belief and religion over restrictions placed on its nationals who wanted to attend the hajj this year. Saudi Arabia's Foreign Minister Adel al-Jubeir said Qatar's complaint amounted to a "declaration of war" against the kingdom's management of the holy sites.
Despite the goodwill measure announced Thursday, tensions remain. The quartet accuses the small Gulf nation of supporting extremists. Qatar denies the allegation and says the charges are politically motivated.
Bahrain on Wednesday said it was investigating an alleged telephone call between Qatar's prime minister and Ali Salman, a Bahraini Shiite opposition leader who is serving a nine-year prison sentence for his role in the country's 2011 protests. Bahrain's public prosecutor said the alleged call centered on how to "exacerbate (tensions) and undermine Bahrain's interests and stability."