The UKIP assembly group leader's description of Welsh Labour's electoral prospects as a "holocaust" was "unforgivable", a Labour AM has said.

Neil Hamilton said Labour would "suffer a holocaust" by losing Welsh seats at the next general election, due in 2020.

He added that he was looking forward to Labour's "blood-letting".

Labour AM Joyce Watson urged him to "spend some time thinking about what the word holocaust really means, in particular to Jewish families".

Mr Hamilton was speaking at his first news conference since UKIP won seats at the Welsh Assembly election in May.

He said his party aimed to replace Labour as the main opposition to the Conservatives at a UK level, and that Wales "offers a lot of scope for this".

"With the boundary changes that are going to take place before 2020, Labour are going to suffer a holocaust, particularly in Wales, and I'm looking forward to the blood-letting which the current leadership contest has been the precursor to," he said.

"That's an opportunity for UKIP to take advantage of."

In response, Mid and West Wales Labour AM Joyce Watson said: "Even by Neil Hamilton's standards, this use of language is absolutely unforgivable.

"He should withdraw these remarks, apologise and spend some time thinking about what the word holocaust really means, in particular to Jewish families in Wales."

Mr Hamilton sparked a row with his maiden speech in the assembly in May when he described two senior female AMs as "political concubines" in First Minister Carwyn Jones's "harem".