Wall Street put the brakes on a recent rally, essentially going nowhere in advance of a Federal Reserve meeting that starts Tuesday.

Benchmark indexes hugged the flatline for much of the session before diverging slightly in the final hour. The S&P 500 was down 0.13%, the Dow Jones Industrial Average added 0.09% and Nasdaq climbed 1.8%.

The central bank's meeting will conclude with a statement and press conference set for Wednesday afternoon. The majority of economists don't expect the Fed to increase interest rates at this meeting after raising them in December for the first time since they were reduced to nearly zero during the 2008 financial crisis.

What will be more important, however, is how the Fed frames its future plans. Members had previously forecast four rate hikes this year at the end of 2015, but that looks less likely after a string of disappointing manufacturing data in the first quarter. 

"Equities are in pause mode and will continue to be in this manner through the Fed meeting and even into early April when companies begin reporting first-quarter results," Terry Sandven, chief equity strategist at U.S. Bank, told TheStreet. "Now we await the Fed's assessment of the pace at which the economy may be growing and to a degree when they may begin further tightening. In our view, equities are likely to remain in somewhat of a trading range over the next month."

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.

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 3.4% to $37.18 a barrel, the lowest settlement since March 8.

Iran said 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 in the markets on Monday. Major oilers 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 0.7%.

Tesla(TSLA) - Get Report boosted the Nasdaq, rising almost 4% after Robert Baird analysts upgraded the stock to overweight. "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.

The tech and consumer sectors were the only ones in the green on Monday. Alphabet(GOOGL) - Get Report , Adobe(ADBE) - Get Report , Netflix(NFLX) - Get Report , McDonald's(MCD) - Get Report , Nike(NKE) - Get Report and Starbucks(SBUX) - Get Report were among the best performers in the sectors.

Alphabet and Starbucks are holdings in Jim Cramer's Action Alerts PLUS portfolio.

In deals news, Starwood Hotels & Resorts (HOT) surged 7.8% 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 supporting a merger with Marriott(MAR) - Get Report .

Fresh Market (TFM) rocketed 24% 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 previously drew takeover interest from Kroger(KR) - Get Report .