Melt the butter in a large pot or Dutch oven over medium heat.
Add the onions, carrots, garlic, salt, and pepper. Sauté, stirring occasionally until onions have softened.
Add the white wine and saffron. Reduce the heat to low, cover, and simmer for 20 minutes.
Add the tomatoes and cook for another minute.
Add the fresh and canned clams with liquid and simmer uncovered for 5 minutes.
Add the milk, and cream. Heat until just heated through but not boiling.
Top with chopped dill.