I'll have to bid 3nt, cant see any other choice. duck 1 or 2 spades and hope atleast one of the minors run. But if both the minors are running, then you have a minor slam, but 3nt will not allow you to investigate that. I can see some proponents of opening 1d with such hands (4-5 in minors), then there is a more comfortable 4c rebid available.