Daniel 2:41-43

The feet and toes you saw were a combination of iron and baked clay, showing that this kingdom will be divided. Like iron mixed with clay, it will have some of the strength of iron. But while some parts of it will be as strong as iron, other parts will be as weak as clay. This mixture of iron and clay also shows that these kingdoms will try to strengthen themselves by forming alliances with each other through intermarriage. But they will not hold together, just as iron and clay do not mix.