* FOMC's two-day meeting starts Tuesday
* Orbital ATK jumps on Northrop Grumman's $7.8 bln buyout deal
* Indxes up: Dow 0.15 pct, S&P 0.17 pct, Nasdaq 0.28 pct (Updates to open)
By Sruthi Shankar
Sept 18 (Reuters) - Wall Street hit new life highs after open on Monday lifted by industrials and financials stocks as tensions eased on the Korean peninsula and focus shifted to the Federal Reserve's meeting.
Caterpillar's 1.8 percent rise was the biggest boost on the Dow while the S&P and the Nasdaq were lifted by Nvidia's 3.6 percent increase.
A relatively quiet North Korea and U.S. Secretary of State Rex Tillerson's comments on "peaceful solution" over the weekend have calmed investors.
However, the tensions could be back in focus with U.S. President Donald Trump set to address world leaders at the United Nations on Tuesday.
The Federal Open Market Committee's two-day meeting starting on Tuesday is unlikely to result in an interest rate increase, but investors will focus on how Fed Chair Janet Yellen views recent inflation readings for clues on the timing of further rate hikes.
The central bank is also expected to announce plans to begin unwinding its $4.2 trillion portfolio of Treasuries and mortgage-backed securities, nearly a decade after the global financial crisis.
"Traders are coming in optimistically given no new geopolitical issues concerning North Korea. They are looking forward to the Fed meeting," said Andre Bakhos, managing director of Janlyn Capital in Bernardsville, New Jersey.
Persistently weak readings of inflation that have remained below the Fed's 2 percent target rate have been a concern for policymakers.
However, a stronger-than-expected rise in consumer prices in August triggered a more than 50 percent rise in the odds of a December rate hike, according to CME Group's FedWatch tool.
At 9:39 a.m. ET (1339 GMT), the Dow Jones Industrial Average was up 33.52 points, or 0.15 percent, at 22,301.86, the S&P 500 was up 4.44 points, or 0.17 percent, at 2,504.67 and the Nasdaq Composite was up 18.27 points, or 0.28 percent, at 6,466.74.
On Friday, the benchmark S&P 500 index closed at a record high, hitting the 2,500 level for the first time, largely helped by a rebound in technology stocks.
Five of the 11 major S&P sectors were higher, led by a 0.58 percent gain in the financial index and 0.56 percent rise in materials index.
Orbital ATK jumped 19.84 percent after Northrop Grumman said it would buy the missile and rocket maker for about $7.8 billion in cash. Northrop's shares inched up 0.70 percent.
Shares of Nabriva Therapeutics soared 90 percent after the company said its drug to treat community-acquired bacterial pneumonia met the main goal of a late-stage study.
Advancing issues outnumbered decliners on the NYSE by 1,705 to 773. On the Nasdaq, 1,596 issues rose and 764 fell. (Reporting by Sruthi Shankar in Bengaluru; Editing by Arun Koyyur)