President Hafez Assad of Syria arrived in Kuwait last night on the third leg of his Middle East tour seeking to explain the hard-line Arab opposition to the Camp David agreements.

Assad arrived in Kuwait from Taif, Saudi Arabia, where he met with senior Saudi officials. Details of Assad's meeting were not disclosed.

Kuwait, although strongly critical of the Camp David accords, was not expected to endorse Assad's views, according to diplomatic sources.

Meanwhile King Khalid of Saudi Arabia left Switzerland for the United States yesterday after meeting an envoy of Egyptian President Anwar Sadat who sought to dispel the king's reservations about the Camp David agreements.

Khalid is to undergo medical treatment in Cleveland.

In Amman, U.S. Ambassador Alfred Atherton met with King Hussein of Jordan for talks about the latest Middle East developments. Atherton is due to leave for Jerusalem today for talks with Israeli officials before going to Egypt.

In Oslo, a Norwegian official said that Sadat has been nominated for the 1978 Nobel Peace Prize for his Middle East peace initiative. The Norwegian official, Jakob Sverdrup, said Sadat's name was put forward by former U.S. secretary of state Henry Kissinger and Austrian Chancellor Bruno Kreisky.