Japan Prime Minister Sanae Takaichi has criticized Russian President Vladimir Putin‘s first-ever visit to the disputed Kuril Islands, saying they were “inherently Japanese territory.”

In a post on X, Takaichi said Thursday that Tokyo had “repeatedly requested the Russian side to ensure that the president does not visit the Northern Territories.” The Northern Territories refer to the Kuril Islands.

She added that Putin’s visit was “absolutely unacceptable.”

The Kuril Islands sit between the southern tip of Russia’s Kamchatka Peninsula and the north-eastern corner of Japan’s Hokkaido. The sparsely populated and volcanic archipelago separates the Sea of Okhotsk from the Pacific Ocean. The four southernmost islands of the chain were annexed by the Soviet Union when it launched an invasion of Japanese territory toward the end of World War II.

During his trip, Putin visited the island of Iturup, where Russia operates a strategically important military base. Russia’s president toured a fish-processing complex, a hospital and a school, before holding a meeting with Valery Limarenko, the regional governor of Sakhalin.

The visit was also criticized by Japanese Foreign Minister Toshimitsu Motegi, who posted on Facebook that “Japan strongly protests this visit.”

Japan renounced “all right, title and claim to the Kuril Islands” in the 1951 Treaty of San Francisco but did not recognise Soviet sovereignty over the territory.

The dispute over the islands had prevented Tokyo and Moscow from signing a peace treaty since the end of the war, although a 1956 joint declaration ended the state of war between the two nations.

Analysts at the Institute for the Study of War, a Washington-based think tank, said that Putin’s visit was likely part of the Kremlin’s response to Japan’s latest defense white paper and aims to undermine Takaichi’s efforts to improve Japan’s defense capabilities.

Japan published its defense white paper earlier in the month, prompting outcry from Putin, as well as Russia’s ally, North Korea. Russia’s president criticized the white paper for identifying Moscow as one of Tokyo’s critical threats.

“Russia is continuing active military activities in the Northern Territories, which…

The U.S.-Taiwan deal aimed at expanding chip production capacity in the U.S. is unlikely to fully wean Washington off the island’s most advanced semiconductors anytime soon, several analysts told CNBC, leaving the so-called “silicon shield” largely intact for now.

Taiwan dominates global chip production, with the Taiwan Semiconductor Manufacturing Company producing most of the world’s advanced chips. Nearly one-third of global demand for new computing power is estimated to be fabricated in Taiwan.   

The island’s central role in the global semiconductor supply chain has made preserving its de facto autonomy — and deterring any Chinese attack — a strategic priority for the U.S. and its allies, an idea referred to as the “Silicon Shield.” Beijing claims territorial control over the democratically-governed island.

As part of a trade deal struck Thursday, the Taiwanese government promised to guarantee $250 billion in credit to its chip and technology companies to expand their production capacity in the U.S. Taiwanese companies will also enjoy higher quotas for tariff-free imports of their chips into the U.S. 

In return, Washington would lower its levies on most goods from Taiwan to 15% from 20%, and waive tariffs on generic drugs and ingredients, aircraft components and natural resources unavailable domestically.

The goal is to bring 40% of Taiwan’s entire semiconductor supply chain to the U.S., Commerce Secretary Howard Lutnick told CNBC on Thursday. But experts doubt the plan would be easy, given Taipei’s hard line on keeping its most advanced technology at home.

Taiwan’s “silicon shield” will remain strong through the end of the decade, with the world’s most critical advanced capacity concentrated on the island, said Sravan Kundojjala, an analyst at SemiAnalysis.

Taiwanese authorities restricted TSMC’s overseas fabrication plants from operating technologies at least two generations behind those developed domestically, known as the N-2 rule.

While TSMC produces its most advanced chips using 2-nanometer technology, or nodes, at home, its Arizona plant has only recently begun producing advanced 4-nanometer chips for U.S. customers, with plans to scale up to 2-nanometer and A16 nodes by 2030. 

In semiconductor manufacturing, smaller nanometer sizes mean denser transistors, which boost processing speed and improve energy efficiency.

That four- to- five-year lag ensures Taiwan retains its advantage, said Kundojjala, adding that the global economy would face a…