Stocks were lower on Monday morning as crude resumed its downward slide on worries over global oversupply. 

The S&P 500 was down 0.34%, the Dow Jones Industrial Average fell 0.16%, and the Nasdaq slid 0.15%.

Crude oil prices were sharply lower after Iranian Oil Minister Bijan Zanganeh said the country wouldn't participate in negotiations with the Organization of Petroleum Exporting Countries next week. Hopes had been high that OPEC members and non-member Russia could agree upon a production freeze in the face of tumbling oil prices, but are unlikely to do so unless all countries are on board. West Texas Intermediate crude oil dropped 2.2% to $37.69 a barrel.

Iran said "that those countries desiring a freeze in output 'should leave [Iran] alone' and allow the nation to regain lost sales and market share in line with its pre-sanctions output levels," Austin Sapp, commodity analyst at Schneider Electric, wrote in a note. "Iran's efforts to ramp up production have reinvigorated the narrative of global oversupply and have therefore struck a blow to the crude complex today."

The energy sector was the worst performer on markets Monday. Major oilers Exxon Mobil(XOM) - Get Report , PetroChina(PTR) - Get Report , Royal Dutch Shell (RDS.A)  and Chevron(CVX) - Get Report were all lower, while the Energy Select Sector SPDR ETF (XLE) - Get Report slid 1.3%. 

The Federal Reserve will convene on Tuesday with an announcement and press conference set for Wednesday afternoon. The majority of economists don't expect the Fed to increase rates at this meeting after making initial liftoff in December. Consensus is for a June hike.

Morgan Stanley analysts disagreed, however, saying they believe that the Fed won't make a move until December. The bank expects Treasury 10-year yields to fall to 1.45% by the end of September, nearing a record low reached in 2012.

It's a busy week of monetary policy elsewhere. The Bank of Japan will meet on Tuesday and the Bank of England will meet on Thursday. The European Central Bank opted to cut rates further and expand its bond-buying program last week. 

Starwood Hotels & Resorts (HOT) surged 8% after receiving an unsolicited buyout offer from a consortium of companies. The bid of $76 a share marks a 7.9% premium to Friday's closing price. The hotel chain's board is currently in support of a merger with Marriott(MAR) - Get Report .

BlackstoneGroup(BX) - Get Report shares were on watch after the company reportedly agreed to sell Strategic Hotels & Resorts Inc. to a Chinese firm for $6.5 billion. Blackstone only completed its acquisition of Strategic Hotels in December.

Fresh Market (TFM) rocketed 22% higher after Apollo Global Management(APO) - Get Report agreed to purchase the grocery retailer for $1.36 billion. The offer of $28.50 a share represents a 24% premium to Friday's close. The company was previously of takeover interest to Kroger(KR) - Get Report .

Tesla(TSLA) - Get Report added more than 1% after Robert Baird analysts upgraded the stock to overweight, arguing that production appeared to be growing. "Although we were concerned about the rate of Model X deliveries, recent data points show production is accelerating, which should drive deliveries and margin expansion," analysts wrote in a note.

Johnson & Johnson(JNJ) - Get Report inched higher after being upgraded to 'neutral' from 'sell' at Goldman Sachs. Analysts also raised their price target to $112 from $102. The firm said the conglomerate was likely to consider restructuring or breaking up in order to unlock potential. 

Walt Disney's(DIS) - Get ReportZootopia topped the weekend box office for a second week in a row, generating $50 million in North America. The animated film has racked up $142.6 million at the domestic box office in the past 10 days.