Dow, S&P 500 and Nasdaq set for opening gains after Friday's 770-point blue-chip fall; Oil extends gain as gold slips. Follow along to the action on Monday aft

Oil prices leapt, and stocks fell on worries that escalating violence following Israel's attack on Iranian nuclear and military targets could damage the flow of crude around the world, along with the global economy.

Markets rebounded after Trump said his administration intends to send letters to US trade partners to formally establish new tariff terms.

The blue-chip Dow Jones Industrial Average was headed for its worst daily drop in almost a month on Friday as the Israel-Iran conflict rattles investors, after easing back from session lows. The Dow was down about 774 points,

The Dow Jones Industrial Average (DJINDICES: ^DJI) index edged 3.9% higher in May, with 70% of its 30 constituent stocks ending the month in positive territory. However, the two worst-performing Dow stocks in May -- both from the healthcare sector -- kept the index's rally in check, with one of them plunging over 25%.

The S&P 500 and the Nasdaq composite index lost more than 1 percent. The Dow Jones Industrial Average fell 1.8 percent, dragged down by three of its 30 stocks.

Shares of Sherwin-Williams Co. and Visa are trading lower Friday afternoon, propelling the Dow Jones Industrial Average selloff. The Dow was most recently trading 822 points, or 1.9%, lower, as shares of Sherwin-Williams Co.

The major averages posted modest gains on Thursday, placing them on track for a winning week. Softer-than-anticipated inflation reports helped lift stocks.