WASHINGTON - US Republican presidential front-runner Donald Trump on Thursday held an unexpected meeting with Republican National Committee chairman Reince Priebus."Just had a very nice meeting with @Reince Priebus and the @GOP. Looking forward to bringing the Party together --- and it will happen!" Trump wrote on Twitter.The meeting at party headquarters in Washington came on the heels of months of tension between Trump and the party he seeks to represent in the Nov. 8 election. Trump on Tuesday abandoned a pledge to support the party's eventual nominee.