Celtic are desperate to strike a permanent £2m summer deal with Newcastle.
But an England call-up could hit their chances - with a likely increased price tag and more clubs taking an interest. Latchford told the Scottish Sun: "Neil Lennon might not be too happy if Stuart Pearce selects Forster.
"That could make keeping the boy all the harder.
"But the main thing is it will show Forster's producing the goods for Celtic."