In this photo released by official website of the office of the Iranian Presidency, President Hassan Rouhani, speaks during a ceremony marking National Space Technology Day in Tehran, Iran, Wednesday, Feb. 1, 2017.

Iranian President Hassan Rowhani said his country sought good relations with its Gulf Arab neighbors as he began a one-day trip to Oman and Kuwait on Wednesday, his first since taking power in 2013.

Relations between predominantly Shiite Iran and the mainly Sunni Arab countries of the Gulf, particularly Saudi Arabia, remain strained over their support for opposing sides in the conflicts in Syria and Yemen.

“The basis of the policy of the Islamic Republic of Iran is always good neighborly relations with neighbors and the security of the Persian Gulf,” Rowhani said, according to the Islamic Republic News Agency (IRNA).

Rowhani also said there should be greater unity between Shiites and Sunnis, saying they had “coexisted side by side peacefully for hundreds of years”, IRNA reported.

Kuwait’s foreign minister made a rare visit to Tehran in late January and called for frank dialogue between Iran and its regional neighbors.

The Iranian president was due to meet Oman’s Sultan Qaboos in Muscat on Wednesday before travelling on to Kuwait on the invitation of its ruler, Emir Sheikh Sabah al-Ahmad al-Sabah, Rowhani’s deputy chief of staff for communications, Parviz Esmaeili, was quoted as saying on Monday by state-run Press TV.