Governor Gavin Newsom of California announced that his state plans to file a lawsuit Monday against Donald Trump for mobilizing the National Guard over the weekend to quell immigration-related protests in Los Angeles.

The swiftly evolving situation in the Los Angeles area over protests surrounding immigration enforcement actions has also cued up a public spat between President Donald Trump and Gov. Gavin Newsom, the California governor who has been one of the Republican president's most vocal Democratic critics.