What taxes does a US citizen need to pay for dividends from a UK company?

Hypothetically speaking, if a UK company has a profit of £300k, it has to pay a 19% UK corporate tax which leaves it with a corporate profit of £243k. If a US citizen was to be paid a dividend of 70% of the £243k profit that would come out to £170k.

What tax and what tax percentage would need to be paid on the £170k dividend paid out by a UK company to a US citizen?