NEW YORK (CNNMoney.com) -- U.S. stocks were poised for a lower open Monday after a weekend in which tensions in the Middle East further simmered.

At 7:30 a.m. ET, Nasdaq and S&P futures pointed to a lower open for the major indexes.

Secretary of State Condoleezza Rice canceled her trip to Beirut after an Israeli air strike killed at least 60 people - including many children - in Qana, Lebanon, CNN reported. (Full story)

Oil prices rose Monday amid uncertainty over the outcome of the conflict. U.S. light crude oil gained 38 cents in electronic trading to $73.62 a barrel, while Brent crude trading in London climbed 61 cents to $74.

Aside from geopolitical worries, financial markets are also gearing up for a week of heavy-hitting economic reports.

On tap Monday is the Chicago purchasing managers' report, due at 10 a.m. ET. Economists surveyed by Briefing.com expect the regional manufacturing index to ease to a reading of 56 in July from 56.5 in June.

But reports on personal income and spending, the Institute for Supply Management's manufacturing index, as well as the closely watched monthly jobs report are all due later in the week.

"This is a blockbuster week for the data-dependent Federal Reserve. This will be the week that makes or breaks the pause question for the Federal Reserve," said Anthony Chan, chief economist with JPMorgan Private Client Services.

Investors may also be recovering from last week's big rally, when the blue-chip Dow Jones Industrial average posted its biggest weekly percentage gain in over a year.

The advance was helped Friday by a report that showed the U.S. economy slowed significantly in the second quarter, and investors hoped the sign of an economic slowdown would sway the Fed to pause its interest rate hiking campaign when it meets next month.

In earnings news, United Airlines parent UAL Corp. (Charts) is set to report its first set of quarterly results since emerging from bankruptcy in February. Analysts surveyed by earnings tracker Thomson First Call expect the company to post earnings of 64 cents a share on revenue of $5.05 billion when it reports before the market open.

Over the weekend, Wal-Mart (Charts) said it expects July same-store sales to come in at the high end of its forecast. The world's largest retailer estimated Saturday that sales for the month rose 2.4 percent.

Treasury prices eased, with the 10-year note yield rising to 5 percent from 4.99 percent late Friday. Bond prices and yields move in opposite directions.

The dollar was lower versus the yen and little changed against the euro.

Major Asian markets finished the session higher, while European stocks were mixed in early trading.

More before the market open