Republican presidential front-runner Donald TrumpDonald TrumpBiden administration still seizing land near border despite plans to stop building wall: report Illinois House passes bill that would mandate Asian-American history lessons in schools Overnight Defense: Administration says 'low to moderate confidence' Russia behind Afghanistan troop bounties | 'Low to medium risk' of Russia invading Ukraine in next few weeks | Intelligence leaders face sharp questions during House worldwide threats he MORE on Monday was spotted grabbing lunch with Edward Klein, the author of several books critical of Bill and Hillary ClintonHillary Diane Rodham ClintonChelsea Clinton: Pics of Trump getting vaccinated would help him 'claim credit' Why does Bernie Sanders want to quash Elon Musk's dreams? Republican legislators target private sector election grants MORE.

Trump, joined by aides Corey Lewandowski and Daniel Scavino, sat for a quick lunch at a delicatessen in Indianapolis, according to The Washington Post.

ADVERTISEMENT

The Post reported Klein was riding in the same vehicle as Trump. Klein said he was following Trump for a couple of days, gathering material for a new book.

Klein’s work on the Clintons has repeatedly come under attack for playing loose with the facts even as it has risen to the top of the best-sellers lists.

Klein wrote a book in 2014 claiming that Hillary Clinton was suffering from a heart problem after previously writing on her husband and former President Bill ClintonWilliam (Bill) Jefferson ClintonBiden must compel China and Russia to act on climate A leadership menagerie of metaphorical scapegoats How Democrats can defy the odds in 2022 MORE's sexual history. 

The meeting comes amid Trump's push to move past rivals Ted CruzRafael (Ted) Edward CruzCruz no longer wearing mask in Capitol The Hill's Morning Report - Presented by Tax March - CDC in limbo on J&J vax verdict; Rep. Brady retiring Democrats brace for new 'defund the police' attacks MORE and John Kasich to clinch the GOP nomination and put his focus on attacks aimed at Hillary Clinton, the likely Democratic presidential nominee.

Trump is campaigning in Indiana ahead of the state's  Tuesday primary.