(CNBC) — Stocks closed flat in a choppy trading session Monday, as gains were limited after a disappointing factory orders report and amid worries over uncertainty surrounding the European debt crisis.

Right around the closing bell, ratings agency Egan-Jones downgraded U.K.’s credit rating to AA- from AA.

“The major problems for the UK is that Europe’s banking crisis does not appear to be abating as evidenced by the miserable results of most EU banks,” according to the company’s report.

Note: Read our discussion guidelines before commenting.