Saudi Arabia on Wednesday welcomed Bahrain's King Hamad, who was warmly greeted by Crown Prince Mohammed bin Salman.
King Hamad met with Saudi King Salman and discussed "bilateral relations and regional international developments", Bahrain's state news agency reported.
"We renew our appreciation and gratitude for the blessed efforts made by Saudi Arabia in serving the Gulf states, Arab and Islamic issues, and for its continued strategic role at the international levels," King Hamad said.
"The efforts by Saudi Arabia are made to ensure a better future for the world."
King Salman held a lunch in honour of King Hamad's visit to the capital. Several members of the royal family also attended.
Saudi Arabia's Foreign Ministry described relations between Riyadh and Manama as "inherent historical links".
Both states have enjoyed close ties for decades.
In most recent years they set up a co-ordination council that has repeatedly stressed the importance of the "historical fraternal relations between the two states and ways to enhance co-operation in various fields".
In December, Prince Mohammed visited Manama and held meetings with leaders.
"The two countries reached a number of initiatives that would enhance co-ordination and consultation in the field of security and military co-operation, cyber security, and facilitating the procedures for transit of goods and trucks across borders," the Saudi news agency reported.
It was the second meeting of the Saudi-Bahraini Co-ordination Council, at Sakhir Palace in Manama.