Oil prices were up about 1 %, bolstered by a confidence that top exporters will this week agree to extend supply curbs, with suggestions that the cuts could even be deepened.
Both benchmarks, Brent crude, and U.S. light crude have climbed more than 10 % from lows hit earlier this month.
President Donald Trump visited Saudi Arabia over the weekend, on his first foreign trip since taking office and one that the White House hopes will shift the focus away from domestic controversies such as his firing of a former FBI head last week and reports of his administration's links to Russia.
The central achievement of Trump's visit was near $110 billion in deals sealed on Saturday in which Riyadh will buy U.S. arms to help it counter Iran, with options running as high as $350 billion over 10 years.
Shares of defense firms such as General Dynamics, Raytheon, Boeing and Lockheed Martin were up between 1.1 % and 3 % in premarket trading and were among the top S&P 500 movers before the bell.
"While the headlines of the Trump visit are overshadowing the geopolitical and domestic political concerns, oil prices are moving higher ... on OPEC expectations," Peter Cardillo, chief market economist at First Standard Financial wrote in a note.
"We see a cautious trading session ahead as investors warm up to commodities."
Dow e-minis were up 28 points, or 0.13 %, with 20,888 contracts changing hands at 8:30 a.m. ET.
S&P 500 e-minis were up 1.75 points, or 0.07 % , with 136,691 contracts traded.
Nasdaq 100 e-minis were up 4 points, or 0.07 % , on volume of 26,056 contracts.
The financial market ended lower last week on concerns about the political storm surrounding Trump's presidency, with investors fretting if Trump will be able to fulfill campaign promises for fiscal stimulus and tax reform.
Many investors saw the policy promises as a key reason for the rally in U.S. stocks since his election win in November.
While the political developments in Washington continue to play on investors' minds, sentiment has been bolstered by the strong quarterly earnings season.
Corporate reports show that, overall, earnings for S&P 500 companies increased 15.1 % in the first quarter, their best showing since 2011, according to Thomson Reuters I/B/E/S.
Amgen fell 2.6 % to $152.50 after the company and UCB SA said they no longer expect their experimental osteoporosis drug to win U.S. approval this year.
Ford was up 2.6 % at $11.15 after the automaker said it would replace its chief executive in response to investors' growing unease over its stock performance and prospects.
Huntsman rose 6.7 % to $28.50 after the company said it and Swiss Clariant are combining to create a chemical manufacturer with a market value of over than $14 billion.