How to resample a 2-D spatial matrix (not a time series) using a weighted average to from the 1km grid to the 0.25 degree

Question

I have a bumpy matrix A with shape [num_X, num_Y]. The corresponding lattitude and longitude array is A_lat (of size [num_Y,1]) and A_lon (of size [num_X,1]). And the each element of this matrix for example A[i, j] represents a value of geophysical variable (for example, leaf area index) at latitude A_lat[j] and longitude A_lon[I].

Now the matrix A is of resolution 1km, while I want to resample it to a resolution of 0.25 degree by using weighted average. So how can I do it? Thanks!