Saudi crown prince Mohammad bin Salman's first official visit to Pakistan has been postponed by a day for 'unknown reasons'.

He was scheduled to reach Islamabad on Saturday, but due to a slight change, he will arrive on Sunday, according to the foreign office.

However, the programmes of his stay in Pakistan will remain unchanged, it said.

Prince Mohammad, who is also the deputy Prime Minister and minister of defence, will be conferred with Nishan-e-Pakistan, the highest civilian award, during his visit to the country, the Express Tribune reported.

Preparations have been made to give an 'unprecedented warm welcome' to the Saudi prince, who will be received personally by Prime Minister Imran Khan and his cabinet members at the Nur Khan airbase, the report said.

Abdul Razzak Dawood, adviser to the Prime Minister on trade, said investment deals worth $10-15 billion would be signed during the trip. On the top of the list is an agreement to set up an oil refinery in Pakistan.

Elaborate security arrangements have been planned during the visit of the powerful heir to the Saudi throne.