The 24-year old has been frozen out by Craig Levein since making himself unavailable for selection in February and Weir just hopes it is not too late to pick up the phone and call the Scotland manager in a bid to get back to representing his country.
"I'm sure Steven has thought long and hard about it. He is a clever boy and a good boy so he knows what he is doing,” Weir told the Sunday Mail.
"He will have his own reasons but my advice would be that if the obstacles aren't insurmountable, make the phone call.
"Do what you have to do to get back involved because we could definitely do with him. There's no doubt about that - Steven has shown he is capable of scoring at a high level.
"We don't have so many good players that we can afford to do without some of our best.
“I would advise Steven to do what it takes to get back in."