Real Dictionary

declare
verb: If you declare something, you state officially and formally that it exists or is the case.
verb: If you declare that something is true, you say that it is true in a firm, deliberate way. You can also declare an attitude or intention.

declare in American English
to make clearly known; state or announce openly, formally, etc.
intransitive verb: to make a declaration
transitive verb: to make known or state clearly, esp. in explicit or formal terms

declare in British English
to make clearly known or announce officially