NatWest customers appear to be having trouble accessing its banking app this morning.

The high street lender has not confirmed what is causing the issue, but some app users say they are being greeted by a message about Sainsbury’s Bank accounts being migrated.

NatWest recently acquired the retail banking business of Sainsbury's Bank, including most of its credit card, personal loan, and savings accounts. The Mirror has contacted NatWest for comment.

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In a post published on X, previously known as Twitter, one person said: "My Sainsbury savings account is transferring to NatWest but I also have NatWest current and savings accounts.

"When I try and use my NatWest app the only option is a link to the transfer Hub and I cannot access my existing NatWest accounts."

Another said: "My banking app has been taken over by the Sainsbury's migration and I am unable to access my NatWest account. Please can you give me a time frame for when it will be fixed."

A third posted: "I’ve logged into my NatWest app, I understand theirs [sic] a Sainsbury’s bank merge, but I’m a NatWest customer who can’t access my own account online either. I have to use the app to authenticate access. Please help."

A fourth person commented: "Hi, I'm a NatWest customer and a Sainsbury's credit card holder? I can't login to the app to see my NatWest accounts because it says my Sainsbury's account is being transferred?!?"

If your bank services have gone down, you aren't automatically entitled to any compensation - it instead depends on how badly the outage has affected you.

For example, if it made you miss a bill or some sort of payment. It also depends on how long the service disruption lasts for and how quickly the bank worked to resolve it.

You would need to put in a complaint if you've been left out of pocket. If you're considering making a complaint, you should gather evidence about how the service issues affected you and for how long.

For example, if it made you miss a bill or if affected your credit score. If you're in desperate need of access to your money but your online services are down, you can go to your local bank branch to withdraw your funds as normal.

If you don’t have a local bank branch nearby or you're unable to get there, try and call your bank or contact it on social media to ask what to do.