RADICAL PROGRAMME
Labour, run by socialist Jeremy Corbyn, makes no secret of its desire to increase the role of the state.
"Labour will tax the rich to pay for things everyone needs and deserves, like decent housing, healthcare and support for our children," McDonnell said.
In a separate interview for the Sunday's Independent he said the party's manifesto would be "the most radical ever" and include a pilot programme for a universal basic income.
The Conservatives currently enjoy a sizeable lead in opinion polls over Labour at the start of election campaigning.
Separate polls for the Mail on Sunday and Observer newspapers both put the Conservatives on 41% support and Labour on 29%, while a Sunday Times poll put the Conservatives on 39% and Labour on 26%.
Both Javid and McDonnell unveiled significant spending plans last week, reflecting a desire to win over voters after nine years of cutbacks under Conservative-led governments.
Like in many advanced economies, British government borrowing costs are currently close to record lows.
But on Friday credit ratings agency Moody's assigned a negative outlook to Britain's sovereign rating, blaming Brexit-related policy uncertainty and a lack of political will to reduce debt.
"The number one thing they point to is this paralysis in decision making, and that is coming from what was a very dysfunctional parliament," Javid said when asked about the Moody's report.
He said the only way to remove the uncertainty was to elect a Conservative government.
Britain's public debt currently stands at around 1.8 trillion pounds, more than 80% of economic output - though below equivalent amounts in the United States, Japan and France.
