Genesis 11:5 And the LORD came down to see the city and the tower, which the children of men builded. 6 And the LORD said, Behold the people is one, and they have all one language; and this they begin to do: and now nothing will be restrained from them, which they have imagined to do. 7 Go to, let us go down, and there confound their language, that they may not understand one another's speech.
Regarding the phrase, "let us go down," in verse 7, Richard Briggs notes that, "theologians have long pondered the plural voice here, so obviously reminiscent of Genesis 1:26..." He writes, "Most OT scholars find the plural "Let us..." language of Gen. 1 and 11 to refer to YHWH's addressing his divine council...." and comments that, "...it may be helpful to read v. 6 as YHWH's "report" to the divine council, in between visits."1
1 Richard S. Briggs, "The Book of Genesis," in A Theological Introduction to the Pentateuch: Interpreting the Torah as Christian Scripture, ed. Richard S. Briggs and Joel N. Lohr (Grand Rapids, MI: Baker Academic, 2012), 39-40