(Reuters) - U.S. stocks climbed on Monday, helped by gains in Apple, Microsoft and Merck & Co, as investors set aside worries about the U.S.-China trade war.

Shares of Apple Inc AAPL.O rose 2.4% after Chief Executive Officer Tim Cook told a German daily that sales of the company's newest iPhones were off to a strong start, while JP Morgan raised its forecast for shipment volumes. Apple is struggling to reverse shrinking iPhone sales amid tepid global demand for smartphones.

Also helped by a 0.9% rise in Microsoft Corp MSFT.O, the S&P 500 technology index .SPLRCT added 1.0%, leading other sectors.

Sentiment on Wall Street got an additional boost after White House trade adviser Peter Navarro dismissed reports that the Trump administration was considering delisting Chinese companies from U.S. stock exchanges as “fake news.”

Concerns related to those reports had sent the S&P 500 .SPX and Nasdaq .IXIC to a more than three-week low on Friday.

“This idea of using different types of levers that impact trade negotiations is something that we will get accustomed to,” said Phil Blancato, chief executive officer of Ladenburg Thalmann Asset Management in New York.

U.S.-listed shares of Chinese firms Alibaba Group Holding Ltd BABA.N and Baidu Inc BIDU.O rose 0.8% and 1.5%, respectively.

The next round of high-stakes trade talks between the world’s two largest economies is scheduled for October.

Wall Street’s main indexes are on course to end September with the weakest quarterly performance so far this year, rattled by a host of factors including an escalation in U.S.-China trade tensions, the inversion of an important part of the U.S. yield curve and political turmoil in Washington.

FILE PHOTO: Traders work on the floor at the New York Stock Exchange (NYSE) in New York, U.S., September 23, 2019. REUTERS/Brendan McDermid

Click here to view the interactive graphic: tmsnrt.rs/2n5vkTu

The Dow Jones Industrial Average .DJI rose 0.36% to end at 26,916.83 points, while the S&P 500 .SPX gained 0.50% to 2,976.73.

The Nasdaq Composite .IXIC added 0.75% to 7,999.34.

For the month, the S&P 500 rose 1.7%, the Dow added 2.1% and the Nasdaq gained 0.5%.

For the third quarter, the S&P 500 and Dow moved up 1.2%, while the Nasdaq dipped 0.1%.

Merck & Co Inc MRK.N gained 1.5% as it presented promising data for its Lynparza cancer drug, which it developed in partnership with Britain's AstraZeneca PLC AZN.L.

Newell Brands Inc NWL.O jumped 2.9% after SunTrust Robinson Humphrey upgraded the household goods maker to "buy."

Investors this week will focus on economic reports, including a key jobs report and the September ISM purchasing managers index (PMI). August’s PMI data showed a contraction in the manufacturing sector.

Advancing issues outnumbered declining ones on the NYSE by a 1.45-to-1 ratio; on Nasdaq, a 1.28-to-1 ratio favored advancers.

The S&P 500 posted 18 new 52-week highs and 1 new lows; the Nasdaq Composite recorded 31 new highs and 117 new lows.

Volume on U.S. exchanges was 6.2 billion shares, compared to the 7.2 billion average for the full session over the last 20 trading days.