How to join summarized tables?

I woul like to know how to join two tables that I get with SUMMIRIZE function. Tables doesn't have a direct relationship, they only connected by common dimensions.
For example, I have the code that doesn't work:

var table1 = SUMMARIZE(
	FactTable1,
	FactTable1[CustomerId],
	FactTable1[DateId],
	FactTable1[CategoryId],
	FactTable1[Amount]
)

var table2 = SUMMARIZE(
	FactTable2,
	FactTable2[CustomerId],
	FactTable2[DateId],
	FactTable2[CategoryId],
	FactTable2[AmountWithDifferentName]
)

return NATURALLEFTOUTERJOIN(table1, table2)

And the execution of this code throws an error message: "No common join columns detected. The join function requires at-least one common join column."