Hi, is it permitted to withdraw out of InteractiveBrokers UK directly to an american broker like tastyworks ?

If they permit residents from your country then, yes. They are not available to all EU.

You would need to open a new acc, KYC/AML all over again. Some people prefer to use US over the Global (UK based) offices because the fees are lower. That does however come with cross currency funding to it adds a bit to deposits/withdrawals.

Which lower fees are you talking about ? For dormant accounts, I only see a difference in maintenance fees for a balance above 2k

NapoleonDynamite 

Which lower fees are you talking about ? For dormant accounts, I only see a difference in maintenance fees for a balance above 2k

Napoleon you are absolutely right. Minimal difference for IB. I was a client of TS Global which is the same office as IB UK and in that case the futures and options for Global were higher and also a higher minimum deposit to open accounts (this have beeen changed last week). So was under the impression the same would apply.