The 26-year-old midfielder has been emerging as a much-sought-after player ahead of the transfer window with several clubs chasing his signature.
Leeds are said to have rekindled their interest in De Paul, who they failed to land last summer, and Liverpool are also considering signing him to bolster their options in midfield.
De Paul also has suitors in Italy with Napoli believed to be keen on taking him to the Stadio Diego Armando Maradona as part of their summer plans.
AC Milan are also interested in De Paul and, according to Italian daily Gazzetta dello Sport, they are prepared to offer a player to Udinese in a bid to beat the competition.
The Rossoneri are ready to dangle the talented young Norwegian Jens Petter Hauge to Udinese to take De Paul to the San Siro.
AC Milan are prepared to offer the winger to Napoli to make it an attractive offer for Udinese.
A player exchange would also bring down the price for De Paul, something AC Milan would be interested in due to the current financial climate.
