Church Action on Poverty and Oxfam have called for a parliamentary inquiry into the rise of food poverty in the UK.

The two charities say that more than half a million people in the UK are hungry and reliant on food aid, with many turning to food banks.

Changes to welfare and delays, errors or sanctions regarding the payment of benefits are two areas they want the inquiry to look into.

In a joint report, Walking the Breadline, the two charities say the most common reason for people approaching food banks is the changes to crisis loan eligibility rules, delays in payments, Jobseeker's Allowance sanctions, and sickness benefit reassessments.

Other contributing factors identified in the report are unemployment, the rising cost of food and fuel, and low and falling incomes.

Oxfam chief executive Mark Goldring said: "The shocking reality is that hundreds of thousands of people in the UK are also now reliant on food aid.

"Cuts to social security have gone too far, leading to destitution, hardship and hunger on a large scale. It is unacceptable that this is happening in the seventh wealthiest nation on the planet."

Further recommendations in the report include the urgent implementation of measures to tackle tax dodging, with the forthcoming G8 meeting in Northern Ireland being asked to promote robust and coordinated international action.

CAP and Oxfam want to see the Department for Work and Pensions publish details of how many households are being affected by benefit delays, errors or sanctions.

All referrals to food banks and other emergency food aid providers through government agencies should be recorded and monitored to establish the numbers of people experiencing food poverty, they say.

Niall Cooper, Church Action on Poverty chief executive and lead author of the report said: "The safety net that was there to protect people is being eroded to such an extent that we are seeing a rise in hunger. Food banks should not be replacing the 'normal' safety net provided by the state in the form of welfare support."

The report has the support of The Trussell Trust, which runs a nationwide network of foodbanks through churches. The trust warned last month that more than 350,000 people received emergency food handouts from its foodbanks in 2012.