1st LD Writethru: U.S. stocks rally on Iran nuclear deal

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

The Dow Jones Industrial Average added 75.90 points, or 0.42 percent, to 18,053.58. The S&P 500 increased 9.35 points, or 0.45 percent, to 2,108.95. The Nasdaq Composite Index advanced 33.38 points, or 0.66 percent, to 5,104.89.

A landmark agreement has been reached over the Iranian nuclear issue between Iran and six world major countries, a diplomatic source confirmed Tuesday.

The comprehensive deal would be sent to the UN Security Council in a short time and it needs to be endorsed by the Council, and the period before the comprehensive deal starts to be implemented by all sides could be around half a year, the source said.

Meanwhile, a draft bill containing prior actions Greece needs to take under the debt deal reached in Brussels on Monday has been tabled in the Greek parliament, according to an official announcement by the Finance Ministry on Tuesday.

The bill which includes a first set of mainly taxation and pension system reforms was scheduled to be put to vote on Wednesday evening.

On the economic front, U.S. retail sales came out weaker than expected. Advance estimates of U.S. retail and food services sales for June were 442 billion U.S. dollars, a decrease of 0.3 percent from the previous month, missing market consensus of a 0.3-percent gain, the Commerce Department announced Tuesday.

"Spending momentum clearly stalled at quarter end, suggesting this year's Q2 bounce didn't have nearly the oomph of last year's, " said Chris Low, chief economist at FTN Financial, in a note.

The reporting season for major U.S. banks kicked off Tuesday. JPMorgan Chase & Co. rose 1.40 percent to 69.04 dollars apiece after reporting better-than-expected quarterly earnings. The bank earned 1.54 dollars per share for the second quarter of 2015 on a revenue of 24.5 billion dollars for the period.

Wells Fargo & Company reported net income of 5.7 billion dollars, or 1.03 dollars per diluted common share, for the second quarter 2015, compared with 5.7 billion dollars, or 1.01 dollars per share, for the same period last year. Its shares increased 0. 90 percent to 57.25 dollars apiece.

Johnson & Johnson announced sales of 17.8 billion dollars for the second quarter of 2015, a decrease of 8.8 percent as compared to the second quarter of 2014. The pharmaceutical firm's shares fell 0.49 percent to 99.78 dollars apiece on Tuesday. Endite