The first mudslinging of the general election campaign has taken place on Newstalk's battle bus in Co Tipperary.

Independent TD Mattie McGrath, Labour Environment Minister Alan Kelly and Fianna Fáil councillor Michael Smith have come to vocal blows over a number of issues.

"You won't bully me in Tipperary for the next three weeks", Minister Kelly told Deputy McGrath on Newstalk Breakfast.

When it came to the issue of the gardaí, host Chris Donoghue was forced to say "Stop shouting at each other, please".

"When we had the resources, we re-opened it and we have put in hundreds of guards inside - in fact thousands of guards in there", Minister Kelly said, referring to Templemore.

But Councillor Smith added: "I think we could have a lot more guards if we didn't have 420 million that was wasted on metres".

And on the issues of Irish Water, Minister Kelly was asked if he thought Irish Water was an election issue, to which he replied: "No, very rarely".

"The biggest issue, without a shadow of a doubt" is jobs, Mr Kelly said.

"You're ringing a call centre in Cork, for a company in Dublin, for a problem out on the road", Councillor Smith said on Irish Water.

And Mr McGrath said: "Irish Water couldn't fix a washer under a sink".