Tunisian President Beji Caid Essebsi defended his decision to welcome Crown Prince Mohammed.
In an exclusive interview with Al Arabiya, Essebsi explained that the founding king advised the late Tunisian President Habib Bourguiba to adopt the politics of stages, which is the policy now pursued by Tunisia at present.
The Saudi crown prince is also facing pressure from different countries that Riyadh announced as part of bin Salman's world tour.
The New York-based rights group said it had filed a submission with Argentine prosecutors calling on them to invoke the country's universal jurisdiction statute to prosecute the crown prince for alleged war crimes committed by the Saudi-led coalition in Yemen.
A banner showing a doctored image of the prince holding a bone saw hung on the headquarters of the Tunisian journalists union.
Erdogan and Prince Mohammed will attend the G20 meeting in Argentina later this week.
In March 2018, Prince Salman visited Cairo for the first time since his appointment as Crown Prince.
Sisi told the Saudi crown prince that the coordination between Egypt and Saudi Arabia should be at the highest level in order to face the current developments and challenges in the Middle East, said the statement.
He was reportedly dismembered in what Saudi Arabia said was a "rogue" operation, but Central Intelligence Agency analysis leaked to the U.S. media pointed the finger at Prince Mohammed. Saudi Arabia also faces a hard situation in which it is necessary to call on true friends.
The Saudi-led coalition, which is backed by the USA, since 2015 has carried out scores of "indiscriminate and disproportionate airstrikes on civilians and civilian objects in Yemen", Human Rights Watch said in its statement.
His visit will be the first by a Saudi royal to Tunisia since the 2011 revolution deposed longtime ruler Zine el-Abidine Ben Ali, who fled to Saudi Arabia. Some critics have likened the Tunisian Ennahda party to the Muslim Brotherhood, which is banned in Saudi Arabia.
Charges would allegedly revolve around Saudi Arabia's prosecution of the war in Yemen and the government's treatment of individual Saudi citizens, prominently including Washington Post contributor Jamal Khashoggi, murdered by Saudi agents at the consulate in Istanbul last month.
Travelling overseas for the first time since the killing, the crown prince is visiting Arab allies before heading to a Group of 20 summit in Argentina this week, where he may face questions about the gruesome slaying.