Chief Executive John Lee has vowed to seize on business opportunities for Hong Kong during his trip to Saudi Arabia and the United Arab Emirates, and to broaden the city's economic and trade cooperation with the region.

Lee left for the Middle East on Saturday, taking with him several of his top officials and more than 30 industry leaders. His delegation will first visit Riyadh, before heading to Abu Dhabi and Dubai.

"Both [countries] are very successful economies," Lee told reporters before leaving the SAR. "They have a great vision and a grand development blueprint in finance, innovation and technology, as well as infrastructure and logistics, and so on.

"Their development vision and needs are exactly in line with Hong Kong's advantages, so Hong Kong can seize a lot of business opportunities. By working together, Hong Kong will broaden its economic and trade development, as well as cooperation with countries in the Middle East."

During his trip, the CE will meet with senior officials, visit local businesses, and attend forums, to tell them about the SAR.

He said Hong Kong can be a beneficial partner to the two Middle Eastern countries on various fronts, such as investment, innovation and technology, and arts and culture.

Separately, Lee said authorities in Hong Kong are fully prepared for the full resumption of quarantine-free travel with the mainland on Monday.

"When we made it clear to citizens that they would have the opportunity to return to the mainland, they travelled according to their own needs and arrangements," he said. "We saw that the daily number of people crossing the border had been steady.

"I believe the full border reopening is very attractive, but the number of people crossing will gradually increase. And they won't have this herd mentality like at the beginning [of the reopening] and swarm to cross the border, worrying that they might not be able to return to the mainland."