The 21-year old has been in good form again this year in Serie A after a breakout season last term, with two goals in 13 appearances for the Zebrette.
Jankto is believed to have been on the Gunners' radar since the summer, although reports of a move to the Emirates Stadium at the start of the 2017-18 campaign were wide of the mark.
According to Calciomercato, however, Arsenal have reignited their interest and are in pole position to sign the Czech Republic international ahead of Juventus and AC Milan.
The report goes on to claim that Jankto's release clause is in the region of £6m and is being considered by Arsene Wenger due to the potential departure of Mesut Ozil, whose contract runs out in the summer.
Jankto has made 43 appearances for Udinese since his 2014 move from Slavia Prague, scoring seven goals and claiming six assists.