U.S. stocks opened flat on Wednesday, but managed to edge higher in morning trading after global shares pared gains on renewed concerns that the U.S. was moving closer to launching military action in Syria.

On the economic calendar, investors will look to July's trade report and vehicle sales figures for the month of August. In addition, the Federal Reserve is scheduled to publish its latest edition of the Beige Book at 2 p.m. Eastern.

The Commerce Department reported Wednesday that the U.S. trade deficit increased 13.3 percent to $39.1 billion in July, compared with expectations for the trade deficit to rise to $38.7 billion, according to economists polled by Reuters.

In earnings news, Dollar General, Navistar and Ciena reported quarterly results before the bell.

Dollar General Corporation (NYSE: DG) reported better-than-expected second-quarter earnings of 77 cents per share, while revenue increased 11 percent to $4.39 billion. Analysts polled by Reuters had estimated per-share earnings of 74 cents on revenue of $4.36 billion.

On Wednesday, shares of Dollar General jumped 5.20 percent to $56.68 in morning trading.

Navistar International Corp. (NYSE: NAV) issued a fiscal third-quarter loss of $2.94 per share, excluding one-time items. Revenue fell 12 percent to $2.9 billion. Wall Street had forecast a loss of $1.30 on revenue of $2.92 billion, according to analysts polled by Reuters.

Shares of Navistar dropped 4 percent to $32.65

Ciena Corporation (NASDAQ: CIEN) said the telecom equipment producer earned 23 cents per share for its fiscal third-quarter, excluding certain items. Revenue rose 14 percent to $538.4 million. Analysts on average had expected earnings of 16 cents on revenue of $533.5 million.

Ciena soared 11.65 percent to $23.09 per share in morning trading.

Looking ahead, investors will focus on the G-20 summit taking place in Russia on Thursday.

The Dow Jones Industrial Average gained 59.58 points or 0.04 percent, to 14,893.54. The S&P 500 rose 8.46 points or 0.52 percent, to 1,648.20. The Nasdaq Composite added 22.12 points or 0.61 percent, to 3,634.61.