Otherwise, it might be recognized as a technically formal declaration of domestic war.

否则，它很可能被认为是一项内战的技术性正式声明。

youdao

Sudan has made no formal declaration of war, but analysts say Mr Kiir is clearly escalating the war of words.

BBC: South Sudan's Salva Kiir says Sudan has declared war

The problem here was that it was not clear that had he asked for a formal declaration of war he would have gotten one.

FORBES: What Happened To The American Declaration Of War?