I simply don't accept Gromit's interpretation that the UK has "lied" about its figures. Not least because the "lie", such as it was, has been exposed by the UK's own figures. The Government was clear that it was counting initially only deaths in hospitals among confirmed cases, and, as a result, was clear that it was under-counting. Later this count expanded to include care home deaths, and later still expanded, I believe, to include deaths in all settings. It's possible I have got the sequence of events wrong, but what is true throughout is that the Government's data sources have been made clear throughout.
The lie from Iran is far more serious because, if the reports are true, then the Iranian Government has had an alternative set of data all along that it has been suppressing. We already knew this -- it was notable, for example, that the all-cause mortality from the early part of the year was released far later than was apparently usual. Accusing the UK Government of lying in the same way is inaccurate; it is quite simply a false equivalence.