Summits are predictable affairs, with leaders sticking to usual protocol and mentioning each other with the official designations. But Prime Minister Narendra Modi went beyond - and some argue against - protocol on Sunday, when he, more than once referred to the US president, as 'Barack' at the joint media appearance.
President Obama, for his part, either referred to his host as either Prime Minister Modi - or Modi.
While former diplomats HT spoke to did not wish to come on the record, there were mixed views on Modi's departure. One school of thought saw it as a mark of personal chemistry, with a former official who has dealt with US commenting, "They spoke about their personal relationship. Americans are rather informal and like this approach. Referring to the president by first name is refreshing."
But another former diplomat disagreed and said that it is best to stick to protocol, especially in summits. "At events of this nature, it is best not to sound too casual and respect the office of the counterpart. Do note that the official text of the opening remarks do not include the reference to the first name and instead sticks to calling him President Obama."