Kerry and Lavrov held informal discussions along with their British, French and German counterparts over coffee after lunch at the French presidential palace, a US State Department official said.
A Western diplomatic source said the talks centred around the crisis in Ukraine and lasted for several minutes.
It was the first time Kerry and Lavrov had met since a pro-Moscow government in Ukraine was ousted, prompting the de facto takeover of the Crimean peninsula by pro-Moscow forces.