Apple Inc. (AAPL) - Get Report shares to a fresh 20-month low Thursday, pulling chip stocks lower and dragging the Nasdaq Composite into to bear market territory, after a shock revenue warning from the world's biggest tech company.

CEO Tim Cook said revenue for the three months ending in December would come in around $84 billion, notably shy of the Street consensus of around $91.5 billion and the company's own previous guidance of between $89 billion and $93 billion. Cook pinned the weaker iPhone demand in China on several factors, including a slowing economy worsened by "rising trade tensions with the United States" and cited high prices tied to the strength of the U.S. dollar, fewer carrier subsidies and customers taking advantage of reduced battery replacements in the softened demand for new iPhones.

"We have been cautious surrounding the newly launched iPhone's ability to drive an upgrade cycle, particularly in China, and December quarter results are worse than we would have expected," wrote BMO Capital Markets analyst Tim Long. "A less compelling new lineup that is priced well above competitive products, coupled with trade tensions, will probably mean more tough quarters ahead for the China business."

Apple shares were marked 8.2% lower at $144.90 Thursday, the lowest since April 2017 and a move that extends the stock's three-month loss to around 38.6% and values the Cupertino, Calif.-based tech giant at just over $690 billion- down from $1.1 trillion on October 3.

Apple alone clipped around 106 points from the Dow Jones Industrial Average (^DJI)  at the opening bell, while the Nasdaq Composite  (^IXIC)   fell 180 points to  take the tech-focused benchmark's slide from its August 29 peak to just over 20%. 

Chipmakers wer also under pressure, with AMD (AMD) - Get Report  down 7.3%, Micron (MU) - Get Report  falling 4.2% and Nvidia (NVDA) - Get Report  sliding 4.2% from their prior close as investors clipped sales and earnings estimates based on a weaker holiday quarter for the world's third biggest smartphone maker.

Apple's German-listed units were marked 8.3% lower at €127.40, while Apple's European supply chain led the tech stock slump, with ASML NV (ASML) - Get Report falling 3.4% in Amsterdam and Austrian chipmaker AMS AG (AMSSY) plunging 20%. STMicroelectronics (STM) - Get Report was marked 8.65% lower while Anglo-German Dialog Semiconductor (DLGNF) fell 8.4% by mid-afternoon trading.

Stocks in Apple's global supply chain were also notably weaker in early trading, with Taiwan Semiconductor Holdings (TSM) - Get Report falling 4.8%, Skyworks Solutions (SWKS) - Get Report down 8.5% and Lumentum Holdings (LITE) - Get Report down 6.8%.

Apple chipmaker Qorvoa (QRVO) - Get Report slumped 8.4% to $58 per share while Universal Display (OLED) - Get Report was seen 8.9% lower at $83.06 each  

Apple CEO Tim Cook said late Wednesday that revenue for the three months ending in December would come in around $84 billion, notably shy of the Street consensus of around $91.5 billion and the company's own previous guidance of between $89 billion and $93 billion.

"While we anticipated some challenges in key emerging markets, we did not foresee the magnitude of the economic deceleration, particularly in Greater China," Cook said. "In fact, most of our revenue shortfall to our guidance, and over 100 percent of our year-over-year worldwide revenue decline, occurred in Greater China across iPhone, Mac and iPad."

Cook pinned the weaker iPhone demand in China on several factors, including a slowing economy worsened by "rising trade tensions with the United States" and cited high prices tied to the strength of the U.S. dollar, fewer carrier subsidies and customers taking advantage of reduced battery replacements in the softened demand for new iPhones.