David Trezeguet admits Sunday's World Cup final will be "difficult personally" as the France World Cup winner with Argentine roots finds himself pulling for Lionel Messi.

Former Juventus star Trezeguet is torn by his loyalties to each country, but his feeling is that Messi deserves to be a World Cup winner and needs this more than Kylian Mbappe.

The Paris Saint-Germain teammates are shaping to be the principal players in the Lusail Stadium drama that will unfold, with 35-year-old Messi seeking his first triumph at this level while 23-year-old Mbappe chases his second winner's medal.

Trezeguet was a champion with Les Bleus in 1998, has elected to play for France, where he was born, over Argentina, from where his parents hailed.

Looking at the position Messi finds himself in, Trezeguet told TyC Sports "I repeat it continuously, for me emotionally, knowing that it will be his last World Cup, Leo deserves to be champion.

"He makes people dream, this does not take away from France's ambition to want to keep the title.

"France came to be world champion, there is no doubt. Here the difference is age, Leo is at the end of his career, Mbappe has just started and will set all kinds of records.

"Together at PSG they are the perfect combination, but Argentina plays for Messi, everything goes through him.

"It's difficult personally, emotionally. Something I didn't want, but hey, this has to be a party and it's a great final. 

"It is what we all expected, due to characteristics, history, they are the two best teams in the World Cup."

Trezeguet could be overtaken by Mbappe on the list of France's all-time highest goalscorers on Sunday.

Presently, Mbappe has 33 goals for his country from 65 games, one shy of Trezeguet's career haul of 34 in 71 international matches.

While Trezeguet will be able to celebrate either victory, there will be broken-hearted players on one side come to the end of the final.

His admiration for Mbappe is fulsome, and Trezeguet believes the forward and his bullish ways only bode well for his long-term prospects.

"He has a healthy ambition, he wants to be better than Messi, that's his motivation," Trezeguet said. "Living in everyday life with Leo and Neymar [at PSG] makes him learn."