Berlin, Feb 20 (DPA) The 60th Berlin Film Festival's main competition comes to an end later Saturday with a solid if at times worthy field of candidates having emerged for the Berlinale's coveted Golden Bear for best movie.

In particular, the frontrunners include Russian director Alexei Popgrebsky's compelling 'How I Ended This Summer' about two men attempting to carve out a relationship of trust against the sweeping landscape of a deserted Arctic island as well as the political thriller 'The Ghost Writer' from Polish-French director Roman Polanski.

However, even if his film does win a prize in Berlin, Polanski is unlikely to be on hand to accept it as the 76-year-old Oscar-winning director is at present holed up in his Swiss chalet facing US extradition moves for a 1977 child sex case.

Among the leading candidates for an award are also Turkish director Semih Kaplanoglu's slow-moving 'Bal' (Honey) about a young boy who goes in search of his father after he fails to return home and Iranian director Rafi Pitts' bleak 'Shekarchi' (The Hunter).

The 42-year Pitts also stars in the movie that tells the tale of a man who turns sniper and kills two policemen in revenge for the death of his wife and daughter, whose deaths were linked to a police shootout with protesters.

Headed up by veteran German director Werner Herzog, this year's Berlinale jury have to select from a 20-film lineup to bestow the festival's top honours, which are to be handed out at an Academy Awards-style gala ceremony.

But the decision-making process of international film festival juries is notoriously difficult to predict with this year's Berlinale main programme including 18 world premieres and three debut features.

Certainly the crop of movies to emerge as favourites for top honours for this year's Berlinale represent something of an improvement on the major contenders for the last two years when the festival delivered a rather lacklustre competition.

However, the earnestness and downbeat themes of many of the entries has led come critics to joke that the festival should add a Grey Bear to its Golden and Silver Bear awards.

But then, the Berlinale has developed something of a reputation for showcasing films with a conscience by screening productions which have hard-edged political and social themes.

In Romanian director Florin Serban's 'Eu cand vreau sa fluier' (If I Want To Whistle, I Whistle), Silviu is a young man facing up to the uncertainties and tensions that have emerged in the wake of the fall of communism across central and eastern Europe.

Silviu is about to leave a juvenile detention centre when he decides that the only way he can stop his mother from taking his young brother to Italy where many Romanians have tried to launch new lives is by sacrificing his own freedom.

The festival has also not been without scandal with the graphic violence in British director Michael Winterbottom's 'The Killer Inside Me' about a murderous Texan sheriff stirring a similar controversy to the one it generated when the movie premiered last month at the Sundance Film Festival in the US.

For the most part, however, the films which have won praise at the festival have been been modern urban dramas such as Danish director Thomas Vinterberg's tale of two brothers caught in a downward spiral of drugs and violence in the almost relentlessly downcast 'Submarino'.

Also several of the films mentioned as candidates for top prizes have explored the impact and sometimes clash of contemporary often western pressures on the Muslim faith, family life and identity.

This includes 2006 Golden Bear winner Jasmila Zbanic's 'Na Putu' (On the Path) where religion becomes a source of conflict in a relationship between a Sarajevo couple as the man moves towards a Muslim fundamentalist view of the world.

Some critics also believe a prize should go to Afghan-German director Burhan Qurbani's well-received 'Shahada', which tells the story of three Muslims who find their faith tested by personal upheavals.