Reneging on purchase deal after mortage has been paid?

A friend of mine agreed with his landlord/owner (a relative) 2007 to pay the mortgage on the verbal agreement that the property would be transferred into his name. Every mortgage payment has been made on time and directly to the bank, since the agreement was made.

Recently the owner has indicated that he wants to sell the property and is trying to get out of the deal which was made when the house was in negative equity and now it is not.

My friend has just had the mortgage payment due on the 1st of May 2019 returned by the Bank lender without explanation and the same happened a second time.

There is nothing in writing re the sale arrangement and no tenancy agreement. The mortgage amount he is currently paying is well below the market rent which in itself confirms that there was a “sale” agreement done.

It is believed the owner is in financial difficulties.

I know there are so many things to consider eg how easy would the bank be able to evict my friend – he has tried to pay the mortgage due this month twice. What a mess!

Any help or ideas very welcome please

Martin