Lancaster and his back-room staff secured their England futures with long-term contracts this week.
That gives England stability ahead of the 2015 World Cup – which they will host – but cast doubt on Lancaster's ability to coach the Lions.
Warren Gatland coached the representative side in Australia last year in one of the most prestigious jobs in rugby.
Lancaster has been mooted for the role for the side's next tour, to New Zealand in 2017, and Rugby Football Union chief executive Ian Ritchie said they would not stand in the coach's way if he is asked to lead the Lions.
"To be honest, I'm not even sure if there's a specific clause in the contracts, but that's irrelevant, because our view of life is that we would be supportive," Ritchie said.
"So if people came knocking on the door, we would regard it as an honour, both for the organisation and for the individual.
"And we would be very happy to deal with that, should it come.
"Undoubtedly when people are asked to be involved everybody should regard it as an honour to be asked.
"The Lions would need to make a request and then we would deal with it, but, in general terms, we would be supportive."