In a multiple regression a very high correlation between predictors would suggest there is an issue of multicollinearity.

Question

Quizplus · Accepted Answer

High correlation between predictors indicates that they are highly related and may be providing redundant or overlapping information to the model, which can lead to unstable estimates of the coefficients and potentially incorrect inferences. This is called multicollinearity.

In a Multiple Regression a Very High Correlation Between Predictors