Islington schools have been defended by teachers after they were ranked worst in London for GCSE results.

The Islington branch of the National Union of Teachers insisted the league tables do not reflect the good work going on in the borough’s classrooms.

Ken Muller, assistant secretary of Islington NUT, said: “League tables don’t tell us how well schools are performing, they simply tell us how well-off their students’ parents are. Islington is one of the most deprived boroughs in the country and this goes a long way towards explaining why it is bottom of the GCSE league table, while Kensington and Chelsea is at the top.”

Despite having the lowest rate of pupils passing the benchmark five GCSE’s at A* to C, including Maths and English, in the capital, Mr Muller added that Islington’s GCSE results have risen “significantly” in recent years.

The percentage reaching this standard has gone up from 32.8 in 2006 to 48.9 per cent this year, while 75.4 per cent got five A* to C grades in any subject.

Mr Muller also said cuts to the education welfare team, which deals with truancy, contributed to the borough having the highest rate of long-term absence in London. Two of 14 education welfare officers were lost this year, as around 1,561 children - amounting to 8.2 per cent of pupils - missed about a month of school time or more.

He added: “The fact that coalition government cuts led to a number of truancy officers being lost has clearly contributed to the problem and made teachers’ work more difficult.”

Cllr Richard Watts, Islington Council’s schools chief, said: “This is another example of the massive damage unfair and unnecessary Tory and Liberal Democrat cuts are doing to Islington.”