There would be no change in current.
The easiest way for me to demonstrate it is like this:
Ohm's law: I = V / R
Original current = (original voltage) / (original resistance)
New current = (0.5 x original voltage) / (0.5 x original resistance)
Cancel 0.5 out of numerator and denominator:
New current = (original voltage) / (original resistance)
So New current = Original current
