(Reuters) - U.S. stocks ended slightly higher on Monday as investors shook off the weekend’s chaotic G7 summit ahead of a week packed with diplomatic events, and a pair of U.S. Treasury Department auctions met with strong demand.

Investors’ bullishness on a positive outcome from Tuesday’s scheduled summit between U.S. President Donald Trump and North Korean leader Kim Jong Un helped the S&P 500 rise, led by gains in utility Sempra Energy. [.N]

Trump, in Singapore for the summit, said the historic meeting could “work out very nicely” as the countries try to narrow differences on how to end a nuclear standoff on the Korean peninsula.

“No one expects anything concrete to come of the meeting ... but if the tone is positive afterwards, it won’t be a headwind for stocks,” said Ken Polcari, director of the NYSE floor division at O’Neil Securities in New York.

The Dow Jones Industrial Average .DJI rose 5.78 points, or 0.02 percent, to 25,322.31, the S&P 500 .SPX gained 2.97 points, or 0.11 percent, to 2,782 and the Nasdaq Composite .IXIC added 14.41 points, or 0.19 percent, to 7,659.93.

Sempra SRE.N proved the biggest driver of the S&P's rally, closing the day up 15.55 percent to $117.20, after two key shareholders recommended six new directors for the company's board and urged a strategic review of its business.

U.S. Treasury yields climbed as the Treasury Department sold $54 billion in new coupon-bearing supply, and on the expectation that the Federal Reserve will raise interest rates on Wednesday.

Demand was strong for the Treasury Department’s $32 billion sale of three-year notes and $22 billion sale of 10-year notes.

The three-year notes sold at a high yield of 2.664 percent, just below where they traded before the auction. Indirect bidders, which include fund managers, some central banks and other investors, took their largest share of the auction since January.

Benchmark 10-year notes US10YT=RR last fell 4/32 in price to yield 2.949 percent, up from 2.935 percent late last week.

The 30-year bond US30YT=RR last fell 6/32 in price to yield 3.091 percent, up from 3.082 percent on Friday.

FILE PHOTO: Traders work on the floor of the New York Stock Exchange (NYSE) in New York, U.S., May 18, 2018. REUTERS/Brendan McDermid

INVESTORS AWAIT MEETINGS

Markets seemed willing to abide a rowdy G7 summit over the weekend in anticipation of the North Korea meeting and other diplomatic and policy events this week.

Trump upset the Group of Seven’s efforts to show a united front, choosing to back out of a previous joint communique. The action drew criticism from Germany and France, and Trump called Canadian Prime Minister Justin Trudeau “very dishonest and weak.”

The Canadian dollar fell about 0.45 percent on the news to C$1.2986, while the Mexican peso shed 1.39 percent to 20.576 pesos per U.S. Dollar.

By and large, though, “markets are generally overlooking negative takeaway” from the G7 meeting, said Peter Cecchini, chief market strategist at Cantor Fitzgerald in New York.

Instead, they are looking ahead to a busy week. Tuesday’s North Korea summit will be followed by meetings of the U.S. Federal Reserve, which is expected to raise rates, and the European Central Bank - as well as a Brexit bill vote in the British parliament.

Also helping calm markets were comments from Italy’s new coalition government that it had no intention of leaving the euro zone and planned to cut debt.

The statements pushed Italian stocks .FTMIB up more than 3.4 percent, while the pan-European FTSEurofirst 300 index .FTEU3 rose 0.72 percent.

MSCI's gauge of stocks across the globe .MIWD00000PUS gained 0.26 percent.

The prospect of Italy remaining in the euro zone also sent Italian borrowing costs down sharply, as the euro EUR= rallied 0.15 percent to $1.1784, not far off a two-week high of $1.1840.

The dollar index, which measures the greenback against a basket of other currencies, .DXY rose 0.03 percent.

In commodities, oil prices fell in early activity, pulled down by rising Russian production, before regaining momentum later.

U.S. crude CLc1 rose 0.55 percent to settle at $66.10 per barrel, while Brent LCOc1 settled at $76.46, unchanged from Friday.