* Deutsche Post says owes authorities value-added tax
* Says to make payment in Q3
* Impact on net profit 265 mln euros, on EBIT 180 mln
* Affirms 2012 EBIT target
* Shares up 0.7 pct (Adds further comments by Deutsche Post, share price)
FRANKFURT, June 5 (Reuters) - Deutsche Post DHL said it owes back taxes of 516 million euros ($644.79 million) which it can only partially offset with provisions made in recent years.
Europe's biggest mail and express delivery company said on Tuesday it will pay the value-added tax ( VAT) f or the years 1998 through 2010 in the third quarter of this year, taking a net profit hit of 265 million euros.
"A large part of the additional payment amount relates to tax issues, for which the Group had already partially formed reserves," Deutsche Post said.
"In addition, the financial authorities had retrospectively examined several postal services for tax liability, which were previously exempt from VAT."
The news comes a week after Deutsche Post said it will have to repay to the German government 298 million euros worth of state aid, including interest, to comply with a European Union ruling made earlier this year.
The impact of the VAT repayment on operating profit will be 180 million euros, but Deutsche Post still affirmed its full-year aim of posting ea rnings before interest and tax (EBIT) of 2.5-2.6 billion euros.
According to the Thomson Reuters StarMine SmartEstimate, which weights analysts' estimates according to their track record, Deutsche Post was so far seen posting 2012 EBIT of 2.63 billion euros.
Shares of Deutsche Post dipped briefly but were up 0.7 percent at 12.89 euros by 0713 GMT, outperforming a 0.5 percent gain by Germany's blue-chip DAX index. ($1 = 0.8003 euros) (Reporting by Maria Sheahan; Editing by Hans-Juergen Peters)