André Villas-Boas is threatening to pull out of talks about replacing Harry Redknapp at Tottenham Hotspur after discovering the club are still speaking to other candidates at the same time as talking to him about the job.

Villas-Boas's information is also that Tottenham will sell Luka Modric to Real Madrid this summer and though that has not put him off the idea of returning to London, the former Chelsea manager is unhappy about what he perceives as mixed signals from White Hart Lane. In particular he is unimpressed the chairman, Daniel Levy, is still considering other options despite holding lengthy talks with him over the past week about taking over from the sacked Redknapp.

The Portuguese has complained to associates that "they are talking to 10 other coaches" and though that is clear exaggeration, it indicates how dismayed he is to learn that Levy has not identified him as the sole candidate.

Levy has had several discussions with Villas-Boas, as well as holding talks with the 34-year-old's representatives, but the headhunting process has also led Tottenham to explore the potential availability of the France manager, Laurent Blanc, as well as Roberto Martínez of Wigan Athletic and Ralf Rangnick, who stepped down as Schalke's coach last September.

Others may be on that list, including David Moyes of Everton, and Villas-Boas demonstrated during Liverpool's search for Kenny Dalglish's successor that he does not appreciate being one of many candidates. Officially, Liverpool's American owner ruled him out before appointing Brendan Rodgers but Villas-Boas had also said he was not interested after discovering he was not their first choice.

Villas-Boas is clearly not short of ego, despite his difficult and unsuccessful spell at Stamford Bridge, and his attitude is that a man who won the Portuguese league title, the domestic cup and the Europa League in his one full season with Porto should not be messed around – as if forgetting that his stint lasting eight and a half months at Chelsea was remarkable only for its bad results and his inability to win over key players.

He has talked of not being made to feel sufficiently wanted by Tottenham and though the situation can be repaired, he has indicated behind the scenes that if it continues he will remove himself from contention.

That puts pressure on Levy to accelerate the talks and, in essence, do more to massage Villas-Boas's bruised pride. Levy is determined to get this appointment right because he knows anything else but a Champions League finish would rebound badly on him next season given that Redknapp had led the club to two fourth-placed finishes and one in fifth in the past three seasons, only missing out on Champions League qualification last month when sixth-placed Chelsea beat Bayern Munich in the final.

Whether Villas-Boas is unhappy enough to go through with his threat remains to be seen, and the Modric situation is not a part of his thinking. The Portuguese, out of work since his sacking at Chelsea in March, is now convinced Modric will leave White Hart Lane. The 26-year-old Croatia international had asked for a transfer a year ago, acutely aware he could earn substantially more elsewhere when Spurs currently operate with a £70,000-a-week salary limit.

Tottenham rejected Chelsea's approaches at the time but Modric still wants to leave and Madrid's interest has been confirmed to Villas-Boas.

Manchester United are also long-term admirers but Modric's former Croatia team-mate Mate Bilic was quoted recently saying he expected the midfielder to move to the Bernabeu.

"I'm very good friends with Modric," said the Sporting Gijon striker. "He wants to play in the Spanish league. He loves the Premier League but he wants to play in Spain. He's very close to agreeing a move."

Vedran Corluka, Modric's team-mate for club and country, has also said during Euro 2012 that he expected the midfielder to go in search of Champions League football, having missed out on Chelsea's triumph last season.