How to use a variable from register in command mode?

Question

I have a list of cities

London
Madrid
Paris
Brasil

I want to write a macro, that will add a ul tag and wrap each city in to an li.

I think, i need to create a variable like:

let i = 4

Than to write macro a(also have macros b, that will wrap each line into li)

qa(call var i)Vc<ul>j</ul>kp(call var i)@b

Answer 1

Doesn't answer the title question, but with https://github.com/tpope/vim-surround, I would do (type literally; angle brackets here are not key notation)

ysip<ul>Vitoj:normal yss<li>

and press Enter.