Manchester United are hopeful of signing Henrikh Mkhitaryan at the weekend for £30m after Borussia Dortmund admitted they had received “a much improved” offer from the Premier League club for the Armenian.

The Guardian reported on Saturday night that United were preparing a £30m bid for the 27-year-old and the Dortmund chief executive Hans-Joachim Watzke admitted on Tuesday that the club had received the offer and that they were seriously considering selling Mkhitaryan, who only has a year left on his contract.

“The situation is now different,” Watzke said. “Manchester have made a much improved offer. In situations like this there are always a lot of different things to consider and in the end at one point we have to make a decision.

“And as we are back in training on Monday we will decide at the weekend. I have contacted the relevant people and we will weigh things up at the weekend. And then the board will make the decision, definitely at the weekened.”

Mkhitaryan, who has attracted the interest of several other clubs, including Arsenal, and has been one of the best attacking midfielders in the Bundesliga since joining from Shakhtar Donetsk in 2013, would be offered a four- or five-year contract.

Dortmund, who have already lost Mats Hummels to Bayern Munich and Ilkay Gündogan to Manchester City, made an unsuccessful £29.2m bid for the Bayer Leverkusen forward Karim Bellarabi last week.

The Bayer Leverkusen sporting director, Rudi Völler, told Bild on Saturday: “There was an official request from Dortmund a few days ago, but it was instantly rejected. To sell Karim is not an option for us at Leverkusen. He is definitely staying, he is not for sale.”

The new Manchester United manager, José Mourinho, has already made one signing, the defender Eric Bailly, who has joined from Villarreal in a £25m deal, and have offered Zlatan Ibrahimovic a one-year contract worth £220,000 a week with the Swede set to meet Mourinho in the first week of July to discuss a possible move.