Heading a high-profile delegation, Rouhani visited Malaysia to attend the 2019 Kuala Lumpur Summit.
During his stay in Malaysia, he held talks with Prime Minister of Malaysia Mahathir Mohamad, Qatari Emir Tamim bin Hamad Al Thani and the Turkish President Recep Tayyip Erdoğan.
He also delivered a speech in a meeting with Iranian nationals in Malaysia.
The Iranian president then left Kuala Lumpur for Tokyo to hold negotiations on bilateral, regional and international issues with the Japanese Prime Minister Abe Shinzo.
Earlier in a Twitter message, Rouhani hailed his fruitful talks in Japan, saying: "I welcome any effort that could boost economic exchanges, especially in the energy sector, and increase oil exports."
He added: "As long as it preserves our national interests and be in the #JCPOA context. Other parties must also keep up to their commitments."
Referring to the 90-year-old relations of Iran-Japan, President Rouhani underlined that a number of visits made by both sides over the last six years are indicative of both sides' constructive ties.
He called for expanding bilateral relations in the fields of energy, science, medicine, tourism, sport, customs, industry and economy as well as trade.
Pointing to the harsh and unlawful sanctions imposed on Iran in the wake of the US withdrawal from Iran nuclear deal, the Iranian president said Washington's pulling out of the international agreements, including the JCPOA has endangered global peace as well as security.
President Rouhani called on all states to honor the United Nations Security Council Resolution 2231, adding that the US sanctions could be regarded as economic terrorism.
The states that combat terrorism should stand up to the US moves, he reiterated.