If you've been watching mortgage rates recently, you may have noticed something that initially seems confusing.

The Bank of England held Bank Rate at 3.75% in September, yet many fixed mortgage rates have become more expensive.

So why are mortgage rates increasing when the Bank of England hasn't increased the Base Rate?

The answer lies in the way fixed-rate mortgages are priced — and, right now, events happening thousands of miles away are having a very real impact on mortgage borrowers here in the UK.

Let's break it down without the financial jargon.