Iran, Berkshire Hathaway earnings, OpenAI's Pentagon deal and more in Morning Squawk

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Good morning. We're coming off a weekend that could have long-term ramifications for world politics, so let's dive in.

Stock futures are tumbling this morning. The market notched a losing day and week on Friday.

Here are five key things investors need to know to start the trading day:

Strikes by the U.S. and Israel overnight on Saturday killed Iran's leader. The mission, named "Operation Epic Fury," resulted in the deaths of multiple American service members and prompted retaliatory hits by Iran.

Here's what to know:

Concern about the conflict spilled into the public markets, with stock futures pulling back sharply in premarket trading. Follow live markets updates here.

Gold futures advanced as investors sought safe havens, while Wall Street's so-called fear gauge jumped to its highest levels of 2026. On the other hand, energy and defense stocks rallied in premarket trading.

Investors were already coming into today's session on their back foot: The S&P 500 and Nasdaq Composite notched their worst months in nearly a year in February. But the Dow Jones Industrial Average eked out a gain for February, marking its longest winning streak since 2018.

In Berkshire Hathaway's last quarter with Warren Buffett as CEO, operating earnings fell nearly 30%. The conglomerate was dragged down in large part by a 54% slide in profits from the insurance underwriting business.

Still, analysts and investors approved of new CEO Greg Abel's first annual shareholder letter. As CNBC's Yun Li reports, they appeared pleased with his commitment to the company's value-focused philosophy and his insight into the capital allocation strategy.

While Abel isn't planning to make major changes to the Omaha-based firm's operations, he did strike a different tone than Buffett had taken in previous letters. See all the highlights here.

Trump forced U.S. agencies to stop using Anthropic's technology after the artificial intelligence startup pushed back against the Pentagon's usage demands. Within hours, Sam Altman, the CEO of competitor OpenAI, said his company struck a deal with the Department of Defense.

Notably, Altman said that OpenAI had the same "red lines" around guardrails on the technology as Anthropic and that the Defense Department agreed to these restrictions. It's not clear why the federal government would accept such requirements from OpenAI but not Anthropic.

But there's a silver lining for Anthropic: The company's Claude AI assistant app jumped to the top of Apple's list of free apps over the weekend. As CNBC's Jordan Novet reports, the climb suggests that Anthropic could be benefiting in the court of public opinion from its pushback to the Pentagon.

Looking for the latest evidence of the so-called K-shaped economy? Look no further than the gym.

Life Time and Planet Fitness both reported solid growth. But as CNBC's Brandon Gomez finds, below-the-surface differences in their earnings underscore the increasing gap in consumers' habits.

At luxury gym Life Time, members are shelling out for higher dues and add-on experiences such as personal training and spa visits. Meanwhile, value chain Planet Fitness' soft outlook raised alarm about how much further price-sensitive consumers can stretch their wallets.

Here's what we're keeping an eye on this week:

— CNBC's Lee Ying Shan, Vinay Dwivedi, Garrett Downs, Greg Iacurci, Azhar Sukri, Spriha Srivastava, Emma Graham, Leslie Josephs, Yun Li, Fred Imbert, Alex Crippen, Spencer Kimball, Dan Mangan, Ashley Capoot and Brandon Gomez contributed to this report. Melodie Warner edited this edition.

Disclosure: Versant Media is the parent company of CNBC.