Lambert sounded off in the summer over what he believed were public overtures from Koeman towards his centre half Ron Vlaar, accusing the Saints boss of 'disrespecting'.
"It's so easy that situation," he explained.
"I spoke one time to a Dutch journalist about Vlaar and nothing more.
"If the manager of Aston Villa likes to take that as a big problem that's his problem and not my problem.
"I think they have bigger problems to think about."
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