Berbatov quit the national team in May citing personal reasons and his absence has been keenly felt during Bulgaria's weak start to Euro 2012 qualifying.
But Matthaeus has pledged to do his best in persuading Berbatov to come back, saying: 'I plan to start talks with Berbatov. He is still welcome in the Bulgarian national team. As a Bulgarian player he should be proud to play for his country.'
Hot streak: Dimitar Berbatov is in fine scoring form for United this season
The 49-year-old former Germany midfielder formally signed a one-year contract on Thursday with an option for two more years. He replaces Stanimir Stoilov, who resigned after defeats to England and Montenegro in the opening Euro 2012 qualifying Group G matches.
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