Wall Street finished off a holiday-shortened trading session on Friday to the downside, slipping from Wednesday's record highs for all three major indexes, as ongoing concerns on the progress in U.S.-China trade talks offset a strong kickoff to the critical retail holiday shopping season. 

The Dow Jones Industrial Average ended down 112 points, or 0.4%, at 28,051.41. The tech-heavy Nasdaq fell 0.5% to 8,665.47, while the S&P 500 dropped 0.4% to 3,140.98. Friday's trading session ended at 1 p.m. after the market was closed Thursday due to the Thanksgiving holiday. Despite the declines from Wednesday's record highs, stocks still put in their best monthly performance since June.

All three major averages posted strong monthly gains, despite Friday's losses. The S&P 500 climbed 3.4% to post its biggest one-month gain since June, when it rallied more than 6%. The Dow and Nasdaq Composite gained 3.7% and 4.5%, respectively, for November.

For the week, the Dow gained 0.6% while the S&P 500 rose 1% and Nasdaq advanced 1.7%.

November was kind to equity investors amid expectations of a rebound in global growth and ongoing U.S. economic strength feeding into the U.S. economy, particularly to companies focused on the all-important U.S. consumer. Talk of a trade deal with China also helped buoy equities, though both U.S. and global markets retrertsd retreated this week after President Donald Trump signed legislation backing Hong Kong's protesters, leaving investors concerned as to the extent of the Chinese response.

The U.S. legislation, signed by President Trump just ahead of Thanksgiving, threatens sanctions against China for human rights violations and seeks to safeguard Hong Kong's autonomy.

With both Washington and Beijing inching closer to a so-called phase one trade agreement, which the president trumpeted as complete earlier this year, the sudden change in tone from the passage of the pro-democracy bill has some investors concerned that talks could collapse before a Dec. 15 deadline on tariff increases.

The negative news was partially offset by initial blockbuster numbers on the retail sales front, particularly online. Shoppers spent more than $4.2 billion online on Thanksgiving, a 14.5% increase from last year and a record high, according to data released by Adobe. As of 9 am E.T., Black Friday online sales were on track to hit $7.4 billion. 

About 46% of those purchases were made on mobile devices, up from 34% a year ago, Adobe said.

Some 165.3 million Americans already have begun shopping or bargain hunting during the holiday, according to the National Retail Federation.

Retail stocks got off to a somewhat slower start on Friday, with the SPDR S&P Retail ETF (XRT) - Get Report  slipping 0.76%. Amazon (AMZN) - Get Report shares were down 0.97%, while shares of Macy's (M) - Get Report  dropped 1.03%. Best Buy (BBY) - Get Report shares were down 0.12%, meanwhile, while shares of Target (TGT) - Get Report  fell 0.71%. Walmart (WMT) - Get Report bucked the trend, with shares gaining 0.28%.

On the non-retail front, shares of Tech Data (TECD) - Get Report  surged more than 12% after the technology distribution company agreed to an improved $6 billion takeover from private equity group Apollo Global Management (APO) - Get Report - a sweetened offer over Warren Buffett's Berkshire Hathaway's (BRK.A) - Get Report reported $130 a share bid made last month.

Apollo said Thursday it will pay $145 a share for the company.

Amazon is a holding in Jim Cramer's Action Alerts PLUS member club. Want to be alerted before Jim Cramer buys or sells AMZN? Learn more now.