Rome: Texas Sen Ted Cruz blasted rival Donald Trump in a radio interview, accusing the Republican front-runner of being a bully, inciting violence and using dirty tricks to intimidate voters and delegates, as Trump continued to rail against a nominating system he says is crooked and rigged.

Using some of the harshest rhetoric of the campaign to date, Cruz said his billionaire rival is a bad businessman who has been surrounded by sycophants his entire career.

“Donald’s whole pitch is he’s a great businessman,” Cruz said in a wide-ranging interview on the Glenn Beck radio show, adding that given how Trump runs his campaign, “it appears he can’t run a lemonade stand.” The comments came as both campaigns work tirelessly behind the scenes to secure delegates who will back them at the Republican Party convention this summer in Cleveland.