Trump's Iran threat, Berkshire's airline bet, Lululemon's proxy battle and more in Morning Squawk

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Happy Monday. My half marathon in Brooklyn over the weekend ended on Coney Island, and all the signage for hot dogs reminded me of a not-so-fun fact: Frankfurters are over 10% costlier than a year ago.

Stock futures are lower this morning. Stocks are coming off a mixed week.

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

President Donald Trump said on social media yesterday that Iran needs to "get moving," as the two countries remain at an impasse in negotiations to end the war. Without progress from Tehran, Trump warned that "there won't be anything left of them."

Here's what to know:

Shares of Delta Air Lines are more than 2% higher before the bell after Berkshire Hathaway unveiled a $2.6 billion stake in the carrier, making it Berkshire's 14th-largest holding as of the end of March. The conglomerate had previously exited the airline sector in 2020 as the Covid-19 pandemic battered travel stocks.

In a new regulatory filing released Friday, the Omaha-based firm also revealed it trimmed its position in Chevron and added to its stake in Alphabet. It also zeroed out stakes in stocks managed by Todd Combs, who departed for JPMorgan Chase last year.

Here's how the stocks Berkshire bought are faring premarket.

Lululemon wrote in a letter to shareholders Monday that activist founder Chip Wilson has "outdated perspectives" and "troubling conflicts of interest" that will derail the retailer's turnaround plan, CNBC's Gabrielle Fonrounge reports.

The letter, exclusively seen by CNBC, is the company's first major public response to Wilson since his proxy battle heated up last year. Materials reviewed by CNBC show settlement talks between Wilson and Lululemon fell apart last week.

The athleticwear retailer in its letter urged shareholders to vote in its favor at the company's annual meeting, which it set for next month, stressing its faith in its strategy, incoming CEO and board nominees.

CNBC's Morning Squawk recaps the biggest stories investors should know before the stock market opens, every weekday morning.

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Meta is expected to lay off about 10% of its staff this week. As CNBC's Jonathan Vanian and Julia Boorstin report, the ongoing cuts have created a feeling of dread among the Facebook parent's workforce.

Workers across the tech industry are watching stock prices soar while, at the same time, their employers are rapidly cutting heads: According to Layoffs.fyi, there have been almost 110,000 layoffs at 137 tech firms so far this year, already nearing the 125,000 cuts made in 2025.

But Wall Street isn't necessarily rewarding AI-related headcount reductions. A CNBC analysis found that among a basket of companies that recently announced layoffs due to AI, the majority of their stocks have dropped since the cuts.

Wondering where Spirit's planes are now that the airline is shut down? There's a good chance they're in the Arizona desert.

Companies like Nomadic Aviation Group have been tasked with getting Spirit's yellow aircrafts from airports across the country to holding areas outside of Phoenix and Tuscon. As CNBC's Leslie Josephs reports, unused or retired planes are typically stored in the desert because the climate reduces the likelihood of damage like corrosion.

It's not an unexpected development. Airlines housed thousands of planes in the desert when travel was at a near-standstill during the Covid-19 pandemic.

Here's what we're following this week:

— CNBC' Garrett Downs, Justina Lee, Fred Imbert, Sean Conlon, Matt Peterson, Jeff Cox, Yun Li, Alex Crippen, Gabrielle Fonrouge, Jonathan Vanian, Julia Boorstin, Liz Napolitano and Leslie Josephs contributed to this report.

CJ Haddad assisted in the production of this newsletter. Josephine Rozzelle edited this edition.