The pair appeared to have a disagreement after the forward headed a late winner for the Netherlands in their Nations League clash against Wales.
At the final whistle, it appeared Weghorst refused to shake hands with Roberts, barging past him, and Roberts seemed to ask the £12m deadline day signing: “Why don’t you do that for Burnley?”
Weghorst responded along the lines of: “This is nothing to do with Burnley, shut up.”
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But, asked after Wales’ 3-2 defeat to the Netherlands in Rotterdam on Tuesday night, whether he had smoothed things over, Roberts said: “No, not yet.”
And, when pushed as to whether he would, he added the barbed comment: “Yeah – if he comes back.”
Weghorst scored twice in 20 games – including from a Roberts assist at Brighton – as the Clarets were relegated from the Premier League, and he is set to leave the club, unwilling to play Championship football in a World Cup year, as he said to Voetbal International while on international duty: “We have clearly agreed in advance that I will not play in the Championship.
"The club would like to keep me and will do everything they can to return to the Premier League as soon as possible.
“For next season it is important that I can perform at a high level, also with a view to the World Cup in Qatar.”