The ambassador noted that everyone is rushing to implement the plan, adding that he thinks everything is moving forward very quickly."But I cannot confirm the date when it will all be completed," he added.

Trump announced on Monday that he had agreed with NATO Secretary General Mark Rutte on a plan under which European NATO countries would purchase weapons from the United States, including Patriot missile systems, and send them to Ukraine.

Several European countries, including Germany, Norway, the Netherlands, Denmark and Sweden, have expressed interest in purchasing weapons for Ukraine. However, questions remain about where exactly these weapons will come from and how quickly they will be delivered to Ukraine.

Whitaker said negotiations will continue on whether the US will sell the Patriot systems it has in its military stockpile.

"We will never put the United States at a strategic disadvantage, and we are going to make sure we have everything we need," the diplomat stressed.

Another option that has been floated is that European countries would send their systems to Kiev now and could prioritize purchasing spare systems from the United States.

US allies are waiting to see what decisions will follow a review of US troop deployments abroad. Washington has warned it could reduce its military presence in Europe to focus more on China.

Whitaker said the United States is in daily discussions with allies about the process, preparing for possible announcements in the coming months.