Holding cash in foreign currencies.

I’ve had a quick look, but can’t find an answer.
If I have a UK account, but intend to use foreign shares, do I need to ‘work’ in the currency?

e.g. I do a rebalance on a pie with all U.S stocks, do I currently pay an FX rate as withdrawal are converted to GBP and back again? Is so, If I had a proprtio of my account in USD funds would I only pay fx when depositing and withdrawing from the USD ro GBP?

Or.

If I sold some U.S stock but intend to buy more of a different U.S. stock at a later date, can I withdraw to USD and keep that until I’m ready to buy ne shares?

I’m guessing that both examples are the same really, just with a bigger time span?

TIA

You can have multi currency in a GIA, not an ISA.

Aside from that you have the option to decide how you manage cash, so yes buying a US stock after selling a US stock, keep your funds in USD to avoid fx fees.

Sorry,

Just seen this. Thank you for your reply.