RFE gives one answer here
With little going on at the EU-Russia summit, the "FT's" Charles Clover has a nice piece looking at why the summit was held in a city nine time zones from Brussels.
Not, you might think, a shrewd effort to befuddle the EU bureaucrats in advance of the gas negotiations, but apparently because Klaus hadn't been there:
The Kremlin, apparently, had not wanted to choose the location for fear of offending powerful regional governors who were gunning for the honour of hosting it, “so they said ‘let the Europeans choose’”, according to an east European diplomat.
José Manuel Barroso, European Commission president, and Václav Klaus, Czech president - the Czechs hold the revolving EU presidency - had a look at the list of prospective sites before Mr Klaus picked Khabarovsk, because “he hadn’t been there before and wanted to see it”, according to a diplomat, who asked not to be named.
The city, like virtually every Siberian frontier town, boasts pleasant tree-lined central streets named after Vladimir Lenin and Karl Marx, numerous parks, statues of Alexander Pushkin and a lapdance establishment that delegates have been advised to steer clear of.
Well I can feel smug then, because I went in 1975 on my Transiberian train trip. Because I wasn't going to Japan or Australia, unlike most foreign travellers in those days, I couldn't go off to Nakhodka, (the port for boats to Japan) or to Vladivostok (a close city in those days). So I stayed at the last place to which I was allowed to travel which was Khabarovsk, for a few days before flying to Tashkent.
I remember it as a rather pleasant typical small Soviet town (as described above, but I don't think lapdancing had been invented in those days). Fish was regularly on the menu in the hotel. Even the hotel staff were friendly which was not usually the case when they found they had to deal with a lone traveller (more money to be made out of groups) who wasn't going to spend vast amounts on vodka.
It was so unspecial that I seem not to have taken any photos at all. Later I recognised the places I had been to appearing briefly in the Russo-Japanese film Dersu Uzala made by Kurosawa. Dersu is a local hunter befriended by a Russian army explorer, who he rescues from a storm. When the hunter is growing old and can no longer hunt, the Russian invites him to stay in his home in Khabarovsk, but he is unable to settle in the town. The film has stunning photography of the landscape and wild life.