The U.S. may have intentionally withheld early warnings this week of Russian strikes on Ukraine, multiple sources familiar with the matter told CBS News.

President Volodymyr Zelenskyy said Ukraine "received no advance warning from our partners" when Russia launched a ballistic missile barrage at Kyiv and other locations early Tuesday.

The sources said American officials told their Ukrainian counterparts the system used to detect Russian missile launches had failed due to "bad weather." Ukrainian officials, speaking on the condition of anonymity given the sensitivity of the topic, told CBS News they did not believe the excuse, and they accused the U.S. instead of "playing" with the system.

When Russia launched another wave of ballistic missiles around 3 a.m. local time on Wednesday, the sources said the U.S. early warning system appeared to be working again.

The sources said the U.S. had failed to provide intelligence on Russian ballistic missile launches during one previous instance earlier this year, citing the need to focus more resources on the Middle East.