As Zardari saw Krishna at the concert hall, he walked up to him and shook hands with the minister last evening.
Krishna also exchanged pleasantries with several Shanghai Cooperation Organisation (SCO) leaders at the concert.
Zardari`s gesture is being seen as a symbolic act by the Indian side given that the Foreign Secretaries of the two countries are scheduled to meet in Islamabad later this month.
Chinese President Hu Jintao, Russia`s Dmitry Medvedev, Kazakh leader Nursurltan Nazarbayev, Uzbekistan`s Islam Karimov, Tajikistan`s Momalii Rahmon and Kyrgyz acting President Roza Otunbaeva were present at the concert.
Iranian President Mahmoud Ahmadinejad also attended the concert.