First Minister Rhodri Morgan has echoed Tony Blair's opinion that London mayor Ken Livingstone should say sorry for a 'Nazi' comment to a Jewish reporter.
Rhodri Morgan: 'It's not that difficult to apologise'
Mr Livingstone has so far refused to apologise for likening an Evening Standard journalist to a "concentration camp guard" at an event on Friday.
Mr Morgan said he could understand how Mr Livingstone could find himself "at loggerheads" with the newspaper group.
He was speaking in Merthyr Tydfil at the launch of an exhibition about WWII.
The touring exhibition is being mounted by the London-based Imperial War Museum.
He referred to his own childhood experiences during the war as well as the experiences of Jewish children in the conflict.
The prime minister has urged the mayor to apologise
Asked about the incident, he agreed that his Labour Party colleague should apologise for his remarks.
He said: "It's not that difficult to apologise. He has obviously got a block about it."
Mr Morgan said he understood how Mr Livingstone could find himself at loggerheads with the Associated Newspapers group, which publishes the Evening Standard and the Daily Mail.
The mayor has claimed to be the victim of a 24-year hate campaign by newspapers, particularly by the Associated Newspapers group.
The row began after Mr Livingstone was captured on tape asking reporter Oliver Finegold if he was a "German war criminal".
Mr Finegold replied: "No, I'm Jewish, I wasn't a German war criminal. I'm quite offended by that."
The mayor then said: "Ah right, well you might be, but actually you are like a concentration camp guard, you are just doing it because you are paid to, aren't you?"
As well as the prime minister, Culture Secretary Tessa Jowell and Jewish community leaders have said Mr Livingstone should apologise.
Tory MP Boris Johnson, however, said Mr Livingstone should not say sorry but "stick to his guns".