U.S. officials are stepping up efforts to build a giant weapons stockpile in Taiwan after examining recent naval and air exercises by the Chinese military around the island, the NewYork Times reports.

But efforts to turn Taiwan into a weapons depot are facing challenges. The United States and its allies are prioritizing arms shipments to Ukraine, reducing their stockpiles, and arms manufacturers are reluctant to open new production lines without a steady stream of long-term orders.

It is also unclear how China might respond if the United States accelerates arms shipments to Taiwan.

U.S. officials are determining the numbers and types of weapons sold to Taiwan, discreetly telling Taiwanese officials and U.S. weapons manufacturers that they will turn down orders for some large systems in favor of more smaller, more mobile weapons. The Biden administration announced Sept. 2 that it had approved its sixth $1.1 billion weapons package for Taiwan, which includes 60 Harpoon coastal anti-ship missiles. U.S. officials are also discussing how to streamline the sales and delivery process.

The United States will not be able to resupply Taiwan as easily as Ukraine because of the lack of land routes from neighboring countries. According to officials, the goal now is for Taiwan to have enough weapons to defend itself until help arrives. Last month, Biden said U.S. troops would defend Taiwan if China launched an unprecedented attack on the island.

U.S. officials have increasingly emphasized Taiwan's need for smaller, mobile weapons that can be lethal against Chinese warships and aircraft and at the same time able to evade attacks, the centerpiece of so-called asymmetric warfare.