U.S. stocks trade mildly higher amid Fed Chair Yellen's testimony

U.S. stocks edged up in the morning session Wednesday, as investors were digesting Federal Reserve Chair Janet Yellen's remarks delivered in the first of her two-day Congressional testimony.

At midday, the Dow Jones Industrial Average edged up 4.07 points, or 0.02 percent, to 18,057.65. The S&P 500 rose 2.19 points, or 0.10 percent, to 2,111.14. The Nasdaq Composite Index gained 11.07 points, or 0.22 percent, to 5,115.96.

The Fed is on track to raise interest rates later this year, as most Fed officials expect the economy to continue to gain growth momentum over the remainder of this year, said Yellen in her testimony Wednesday.

Low oil prices and ongoing employment gains should continue to bolster consumer spending, while financial conditions generally remain supportive of growth. In addition, the highly accommodative monetary policies in other countries should work to strengthen global growth. Those factors would support the U.S. economy to continue expansion, Yellen said.

However, she reiterated the pace of rate hikes would likely be gradual.

On the economic front, the U.S. Producer Price Index (PPI) for final demand advanced 0.4 percent in June, beating market consensus of 0.3, the Department of Labor reported Wednesday.

U.S. industrial production increased 0.3 percent in June, according to the Federal Reserve Wednesday.

Overseas, a landmark agreement had been reached over the Iranian nuclear issue between Iran and six world major countries Tuesday, ending 12 years of tough negotiations.

Under the deal, sanctions imposed by the United States, the European Union and the United Nations will be lifted in return for Iran accepting long-term cuts to its nuclear program.

In Europe, the European Commission (EC) on Wednesday proposed to grant Greece a three-month bridging loan worth 7 billion euros from a 28-member backed EU-wide fund to address Athens' urgent financing need.

Meanwhile, a draft bill containing prior actions Greece needs to take under the debt deal reached in Brussels, Belgium, Monday has been tabled in the Greek parliament, which was scheduled to be put to vote Wednesday evening.

U.S. stocks posted gains for the fourth straight session Tuesday, as investors were encouraged by the Iran nuclear deal while digesting economic data and the second-quarter earnings reports from big companies. Endite