* Net loss seen for Q4
* Full-year pretax down from 1.4 to just over 1 bln eur
* Bank to pay dividend for 2012 (Adds details, background)
VIENNA, Jan 31 (Reuters) - Austria's Raiffeisen Bank International expects a net loss for the fourth quarter of 2012 due to writedowns of its Ukrainian unit and other assets and a tough economy.
The bank, one of Eastern Europe's leading lenders, also said late on Thursday it expected 2012 pretax profit of slightly above 1 billion euros ($1.36 billion), down from 1.4 billion in 2012 and well below analysts' estimates.
Net profit is seen at over 700 million euros ($950 million) for the full year, after a profit of 842 million euros for the first nine months, Raiffeisen said in a surprise preliminary results announcement.
Analysts were expecting a net profit of 744 million euros and pretax profit of 1.26 billion on average for the year, according to ThomsonReuters StarMine, which weights forecasts according to analysts' past accuracy.
"The economic environment in the fourth quarter proved to be more challenging," Raiffeisen said.
Due to a 30 million euro writedown on a derivatives position, Raiffeisen's proprietary trading operations were not able to contribute to group profits during the fourth quarter.
The bank added, however, it would pay a dividend for 2012.
Chief Executive Herbert Stepic said in November he expected bad loans, which already accounted for a 10th of the bank's lending portfolio, to keep rising into 2013 as the euro zone crisis hurt trading partners in Eastern Europe.
On Thursday, the bank said it had written down its remaining 29 million euros of goodwill on its Ukrainian unit, and another 10 million euros for other assets, in the fourth quarter.
Raiffeisen's Austrian rival, Erste Bank, is selling its loss-making Ukrainian unit after six years in which it lost 250 million euros, and other European banks have quit the country due to slowing growth and political uncertainty.
Raiffeisen said net provisioning for impairment losses in 2012 would be slightly lower than in 2011, when it was 1.06 billion euros. The highest provisions were in Hungary, Poland and Ukraine.
The bank added that general administrative expenses excluding its Polish unit were similar to 2011's 3.12 billion euros, and loans to customers stood at 83 billion euros at the end of 2012, up from 82 billion at the end of 2011.
Raiffeisen will publish more detailed figures on Feb. 20, and its annual report on April 10. ($1 = 0.7367 euros) (Reporting by Georgina Prodhan in Vienna and Christiaan Hetzner in Frankfurt; Editing by Anthony Barker and Jim Marshall)