WATCH: Pentagon holds briefing on Chinese nuclear warheads, Ukraine aid

The Pentagon warned in a new report that China is rapidly modernizing its nuclear force and is on track to have 1,500 active warheads by 2035.

Watch the briefing in the player above.

Pentagon spokesman Air Force Gen. Patrick Ryder said, “the report plays a vital role in informing our understanding of our pacing challenge, and it shows, again why the national defense strategy is laser-focused on the right issues and on the operational concepts, capabilities, and resources we need today and into the future.”

China has already stated its goal to have a military powerful enough to be able to take Taiwan by force, if necessary. China has cautioned the U.S. against coming to Taiwan’s defense.

Last year, the Pentagon said the number of Chinese nuclear warheads could increase to 700 within six years and may top 1,000 by 2030.

The new report says China currently has about 400 nuclear warheads, and that number could grow to 1,500 by 2035. The United States, by comparison, has 3,750 active nuclear warheads.

“The challenge here is the more proliferation there is, the more concerning it is, the more destabilizing to the region it is,” Ryder told reporters in a briefing Tuesday.

Also highlighted, NATO Secretary-General Jens Stoltenberg says war-torn Ukraine will one day become a member of the world’s largest security alliance.

It’s a commitment that NATO leaders made to Ukraine 14 years ago. But some say it led in part to Russia’s invasion.

Stoltenberg’s remarks came as U.S. Secretary of State Antony Blinken and his NATO counterparts gathered Tuesday in Romania to drum up urgently needed support for Ukraine, including deliveries of electrical components for its devastated electricity network.

READ MORE: NATO reaffirms commitment to Ukraine, promises future membership

Ukraine’s grid has been battered since early October by targeted Russian strikes. Some countries also promised military aid, including artillery and armored vehicles.

Beyond Ukraine’s immediate needs, NATO wants to see how it can help the country longer-term, by upgrading its Soviet-era equipment to the alliance’s modern standards and providing more military training.

Ukraine, for its part, called for more supplies of weapons to defend itself with, and quickly including Patriot missiles. While Ukraine has asked for the system for months, the U.S. and its allies have been hesitant to provide it to avoid further provoking Russia.

However, Ryder said, “Air defense continues to be a top priority for DOD and for the international community when it comes to supporting Ukraine. In terms of any type of Patriot battery from the U.S., right now, we have no plans to provide Patriot batteries to Ukraine.”

The U.S. announced $53 million to buy electrical parts for Ukraine’s electrical grid.

The network has been battered countrywide since early October by targeted Russian strikes, in what U.S. officials call a Russian campaign to weaponize the coming winter cold.

On another matter, U.S. and Kurdish military officials say Turkish airstrikes and a threatened ground invasion in northern Syria are impacting their joint operations against the Islamic State extremist group.

Mazloum Abdi, the commander of the Kurdish-led Syrian Democratic Forces in northeast Syria, tells reporters that the group’s joint counter-IS operations alongside the U.S.-led international coalition have been “temporarily paused” because of the recent Turkish airstrikes, and that gains made in the fight against the extremist group to date may be “threatened.”

Ryder says the U.S. has cut back on the number of “partnered patrols” it is carrying out alongside the SDF.

“They have reduced the number of patrols that they’re doing, and so that therefore necessitates us to reduce the patrols,” he said.

However, he added, “We’ve not redeployed any of our folks. We continue to stay very focused on countering the ISIS threat.”