After six years, the first summit between Trump and Putin concluded hastily, lasting only about 3 hours before it was announced to be over, and the originally scheduled lunch was canceled at the last minute, with Putin immediately returning to Russia on a special plane.
The format of the talks was adjusted from one-on-one to three participants from each side, with the U.S. side including Secretary of State Rubio, and the Russian side including Foreign Minister Lavrov. Taking advantage of the venue, Trump used both soft and hard tactics on Putin, and both sides did not explain the reason for canceling lunch, speculating it may have been to expedite the implementation of results or for security considerations.
It is noteworthy that the adjustment of the meeting format may have been pushed by the EU and Ukraine, aimed at containment; if the outcomes of the talks are not recognized by Ukraine, the difficulty of further progress will be significant. Putin's return home may be to deploy more 'bargaining chips' to pave the way for the next Moscow summit.