Efficient way to Remove Item from the List

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LINQ

So, I have a two un-ordered list - result1 and result2 as listed below.
By using a code below I am able to populate result1 excluding the common items between those two lists.
This code works perfectly for the small size list. However, in real scenario I have two lists with millions of item on it. Using the similar way of eliminating the common values from one list into the other list is taking way too much time.
So, I was wondering if there is an more efficient way to deal with this kind of scenario.

List<int[]> result1 = new List<int[]> { new int[] { 1, 2, 3 }, new int[] { 4, 5, 6 } };
List<int[]> result2 = new List<int[]> { new int[] { 2, 1, 3 }, new int[] { 7, 8, 9 } };

result2.ForEach(t => result1.RemoveAll(z => z.OrderBy(k=>k).SequenceEqual(t.OrderBy(k=>k))));