STOCKS ARE FALLING - DOW DOWN 100
The S&P 500 is down 11 points, or 0.5%, and the Nasdaq is down 23 points, or 0.5%.
President Obama is set to speak on Ukraine shortly, after John Kerry over the weekend said that a "mountain of evidence" points to Russia being responsible for the downed Malaysia Airlines flight on Thursday.
The economic calendar was light to start the week, with just the Chicago Fed's national activity index coming in at 0.12 earlier this morning, below expectations for a 0.18 reading.
In corporate news, Halliburton and Hasbro were among the notable companies reporting earnings before the market open today.
Halliburton shares were up 0.6% after the company reported earnings per share that grew to $0.91 from $0.73 the prior quarter.
Hasbro shares were down 2.5% after the toymaker reported revenue that fell short of expectations.
Allergan shares were also up more than 2% after the Botox-maker reported earnings and revenue that beat expectations and announced plans to cut up to 1,500 jobs as part of a restructuring plan.