Solve an equation in mathematica without replacing the value of the parameter

Suppose I want to solve a simple equation in mathematica x-a=0.So I am writing the mathematica code for this as below:

Solve[x - a == 0, x] 

So the output will be as below:

{{x -> a}} 

Now suppose I have assigned a value for ‘a’ beforehand and then want to solve the same equation.So my code will look like below:

a = 1; Solve[x - a == 0, x] 

And the output in this case will be like below:

{{x -> 1}} 

Now if I want an output in this case as {{x -> a}},what modification should I do in my code ?

Note: Clear[a] will work,but I don’t want to remove permanently the assigned value to a