The Old Trafford outfit were close to signing him in 2013-14 when David Moyes was in charge. Kroos had agreed on terms with Manchester United before opting to join Real Madrid instead.
According to Independent, Kroos and Griezmann are two marquee targets for Jose Mourinho this summer.
The report adds that Kroos is considered as ‘un-sellable’ by the Bernabeu hierarchy, but Manchester United will make an effort anyway.

Furthermore, Independent claims that Griezmann’s move to Old Trafford is doubtful as well. Apparently, the French forward wants to see if United can finish in the top four. Griezmann is also keen on finding out the extent of Real Madrid’s interest in him.
However, they have revealed in their report that Manchester United agreed on personal terms with the French star’s representatives towards the end of January.
The Premier League giants are keen on signing the two stars to maintain their commercial value and will make a move for Kroos regardless of what happens with Griezmann.
It will be interesting to see if the 27-year-old German decides to accept Manchester United’s offer in the summer. It is highly unlikely that Real Madrid will want to sanction the sale, especially after the Paul Pogba saga.
Manchester United managed to beat Real Madrid and their financial muscle last summer to secure the services of the French midfielder.

Source : http://www.u2gossip.com.ng/2017/02/manchester-united-latest-talk-with-toni.html?m=1