Great Britain finished their first competition in nine years with a 15-4 loss to Germany at a qualification event in Otopeni, Romania.
The team have not competed since the 2014 European Championship qualifiers because of restructures and reforms in the sport, say British Swimming.
Britain lost all four of their games at the event, which ran from 9-12 March.
As well as their defeat to Germany, they were beaten by Romania, Ukraine and Malta.
The results in the World Aquatics Mens Water Polo World Cup B Division Continental Qualification event mean Britain will not take part in the division 2 World Cup in Berlin, to be held in May.
UK Sportwithdrew its fundingfor water polo in 2014 as one of four sports to lose financial support, along with synchronised swimming, basketball and weightlifting.
Renewed funding from UK Sport has enabled the team to start competing again and the organisation part-funded Britains trip to the qualifying event in Romania.
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