Image caption Are charities being 'hammered' by the regulations on lobbying?

More than 100 charities have written to the government calling for the Lobbying Act to be overhauled.

Age UK, Greenpeace and Girlguiding are among those to claim legislation passed in 2014 stopped them from "engaging" during the general election campaign.

The act limits how organisations not deemed to be "party political" can campaign during election periods.

Charities say they either have to take expensive legal advice to stay within the rules or restrict their activities.

Other voluntary organisations to sign the letter include the RSPB, the Royal Mencap Society and Action for Children.

They criticise the Transparency of Lobbying, Non-Party Campaigning and Trade Union Administration Act for failing to define non-party campaigning properly and say it is forcing them to restrict their campaigning activities to avoid falling foul of spending limits.

Image copyright AFP Image caption Greenpeace, which campaigns on controversial issues, has signed the protest letter

One of the signatories to the letter, Julie Bentley, chief executive of Girlguiding said: "All of society loses out when the voices of those affected by issues are silenced from the debate around solutions, at the very time that decision-makers are listening most intently."

Charities such as Greenpeace have also complained that in-house lobbyists, who handle the bulk of lobbying for business interests, are not covered by these restrictions.

'Burdensome'

The letter calls on the Minister for Civil Society, Tracey Crouch, to reform the Lobbying Act to reduce the burden on charities during election periods.

It describes the act as "a confusing and burdensome piece of legislation that weakens our democracy, rather than strengthening it".

It also claims that it "caused many organisations not to engage in the run-up to the recent general election, and resulted in some important voices being lost from public debate".

Image copyright Getty Images Image caption There were protests against the lobbying legislation when it went through Parliament in 2013

Charities warned of potential difficulties with the legislation when it passed through parliament in 2013.

At the time, Labour MPs called the legislation "risible and misconceived", predicting that it would give a "hammering" to the voluntary sector.

Charities are now renewing their calls for a re-think from ministers.

"Charities will continue to be silenced on a whole range of issues affecting the people they are trying to help, whether it be discrimination and inequality, or climate change, unless our repeated calls for the Lobbying Act to be overhauled get a response," says Tamsyn Barton, chief executive of international development charity Bond, which is coordinating the letter.

Thomas Hughes, executive director of freedom of expression charity Article 19 said: "The UK Lobbying Act runs counter to numerous aspects of freedom of expression and the right to information.

"The ability of charities to express and exchange ideas with those in power, and to propose solutions to challenging problems, enables civil society as a whole to affect change and demand accountability. This role must be enhanced and protected rather than restricted."

A Cabinet Office spokesperson said: "The rules on campaigning at elections in the Transparency of Lobbying Act have never prevented charities or other organisations from campaigning on behalf of those they represent."