This is the 9980th most frequent Russian word.
антибелорусские
"Anti-Belarusian" – opposing or hostile toward Belarus or Belarusians.
The adjective 'антибелорусские' describes the nature of the statements as opposed or critical to Belarus or its people.
Политик сделал антибелорусские заявления.
The politician made anti-Belarusian statements.
Here, the word 'антибелорусские' modifies 'санкции', indicating that the sanctions seem to be against Belarus or its interests.
Некоторые санкции были восприняты как антибелорусские.
Some sanctions were perceived as anti-Belarusian.
In this sentence, 'антибелорусские' qualifies 'настроения', pointing to sentiments that are hostile or negative toward Belarus.