Crown Prince Mohammed bin Salman was expected at Dubai's Expo site, after meeting and dining with Abu Dhabi Crown Prince Mohamed bin Zayed on Tuesday.

His visit, ahead of a Gulf summit, comes as French authorities check the identity of a man who was arrested in Paris on suspicion of playing a key role in Khashoggi's murder.

The journalist, a critic of Saudi authorities, was strangled inside the Saudi consulate in Istanbul in October 2018.

However, Saudi Arabia said the suspect was a victim of mistaken identity as his name, Khaled Alotaibi, is common in the kingdom.

A man named Khaled Alotaibi is one of the 26 on trial in absentia in Turkey for being part of the hit squad that carried out the Khashoggi murder. He has also been sanctioned by the US Treasury for his role in the killing.

The arrest was made at Paris's main airport just days after French President Emmanuel Macron met the Saudi crown prince in Riyadh, dismissing accusations that his visit was effectively condoning Khashoggi's murder.

The Saudi crown prince arrived in the UAE from Oman, where the two sides signed deals totalling $30 billion, and will also visit Bahrain, Kuwait and Qatar.

Security was tight at Expo, where the lavish Saudi pavilion was closed to visitors and a small crowd of onlookers, including women in black robes, gathered outside.

Saudi songs, including one with the lyrics "Welcome Mohammed", were playing on the loudspeaker at Al Wasl Plaza, Expo's central venue.

"The excellent relations between our countries keep growing stronger," Abu Dhabi's crown prince said after meeting his Saudi counterpart on Tuesday, according to the UAE's official WAM news agency.

"Saudi Arabia has been, and will always be a key regional player."

The Saudi prince's visit to Doha will be the first since the two sides severed ties four years ago at the start of a blockade of Qatar that was only resolved in January.