The premier organised a meeting between Qatari Amir Hamad bin Khalifa al-Thani and Riyadh governor Prince Salman bin Abd al-Aziz on a yacht off Monte Carlo Wednesday, the Kuwait City-based al-Qabas daily quoted a ministerial source as saying on Thursday.
Al-Sabah left Kuwait for France late on Wednesday on a three-day "private visit", the official KUNA news agency had reported earlier.
The current chairman of the six-nation Gulf Cooperation Council, Kuwait has a strong interest in resolving the row between the two GCC members, which prompted Saudi Arabia to block construction of a pipeline across its territory through which Kuwait had wanted to import Qatari gas.
The dispute began in summer 2002 when Aljazeera satellite television network aired a discussion in which participants strongly criticised the Saudi royal family.
Riyadh recalled its ambassador from Doha in September of that year and Saudi Crown Prince Abd Allah boycotted a GCC summit in the Qatari capital.
A meeting between the crown prince and the Qatari amir on the sidelines of a GCC summit in Kuwait last December failed to mend fences.