Tottenham have reportedly set a deadline for Celtic to make their move to land Cameron Carter-Vickers on a permanent deal.
The centre-back was one of the stand-out performers at Parkhead for the newly-crowned Premiership champions.
That form has caught the eye of English Premier League sides but Celtic still hold the option to make the deal permanent this summer.
But Spurs appear willing to open the door to a bidding war with American outlet SBI Sport claiming Everton, Fulham and Bournemouth are all keen on the defender.
Tottenham are said to have given Celtic until 15 June to complete a deal for the USA international.
That means a deal may have to be competed during a busy international spell for Carter-Vickers after his first call up in three years.
Gregg Berhalter has given the defender the chance to make his case for a World Cup call up during two friendlies against Morocco and Uruguay and two Concacaf Nations League games, with the first clash on June 2.
Carter-Vickers lifted both the Premier Sports Cup and title during his first campaign, as well as being included in the PFA Team of the Year and being nominated for the Scottish Football Writers' Player of the Year award.
