Some on social media thought first lady Melania Trump looked horrified after shaking hands with Russian President Vladimir Putin at his summit with US President Donald Trump in Finland on Monday.

The three posed for a photo before the two presidents' one-on-one meeting and joint press conference.

Watch the full moment below.

Some on social media said first lady Melania Trump looked horrified and shocked after shaking hands with Russian President Vladimir Putin at his summit with US President Donald Trump in Finland on Monday.

Video of the interaction shows Melania initially smiling at Putin, then striking a face some perceived to be expressing bewilderment and discomfort as she and the two presidents posed for a photo.

One person said Melania was "the only one in the room who realises how dangerous this man really is," referring to Putin. Putin and Melania, who is from Slovenia, both hail from eastern Europe.

Others on social media, however, thought the reactions to the viral video of the interaction were overblown, saying Melania was simply trying to put on a serious face for the photo.

The photo was taken before the two presidents' nearly two-hour one-on-one meeting, which was followed by a press conference.

Watch the video here: