"Two democracies and a defining partnership of our era! PM meets President Obama @POTUS on sidelines of EAS," External Affairs Ministry Spokesperson Vikas Swarup tweeted.
The meeting was "extremely warm and cordial", Swarup said after the meeting. This could be their last meeting as leaders of the two countries with Obama's second term as US President coming to an end in November.
They met for the first time at the White House in September 2014 when Modi travelled to Washington DC at the invitation of Obama.
Modi had also exchanged views with Obama on the sidelines of the G20 summit in China's Hangzhou on Sunday, with the US president praising the "bold policy" move on GST reform in a "difficult" global economic scenario.