O'Sullivan won two silvers in last year's European Championships

Sonia O'Sullivan has given up all hope of competing in next month's World Cross Country Championships in Lausanne.

The Olympic silver medallist has been unable to train in recent weeks because of an Achilles tendon injury.

She attempted to resume sessions last week but has now admitted defeated and flown from her training base in Australia to see her physio Ger Hartmann in New Mexico.

O'Sullivan helped the Irish women's team claim a bronze medal in last year's short course event in Dublin and her absence will be a huge blow to the country's chances of making an impression in Lausanne.

Hartmann said that the injury would take "three to five weeks of treatment to heal" but is confident that the athlete will be fit for the summer track season.

O'Sullivan suffered a similar Achilles injury in the early part of 1995 but went on to claim the World 5000m championship later in the year.

The Cobh runner won two silver medals at last year's European Championship but then suffered a somewhat chastening experience when finishing a distant 12th in the New York Marathon.