The Jo Cox Foundation has called on all political parties to agree to a code of conduct to help protect MPs.
It comes after the prime minister was accused of using language that could "incite violence" in a Commons debate.
Boris Johnson went on to suggest the best way to honour the murdered MP Jo Cox, who had wanted to remain in the EU, was to "get Brexit done".
Her husband, Brendan Cox, has said he was "shocked" by the type of language used in the Commons on Wednesday.
Mrs Cox, a mother of two, died in 2016 after she was shot and stabbed while on her way to meet constituents in Birstall, West Yorkshire.
During the debate, Mr Johnson dismissed a complaint by one Labour MP that his rhetoric risked provoking attacks on politicians as "humbug".
He was also challenged over his use of the words "surrender bill" and "surrender act" to describe legislation passed earlier this month which aims to block a no-deal Brexit on 31 October.
Following the criticism, Mr Johnson insisted he "deplores any threats to anybody, particularly female MPs" and acknowledged that "tempers need to come down".
The foundation set up in memory of Mrs Cox said it has been working with the Committee on Standards in Public Life (CSPL) to develop a "joint standard of conduct" to help protect election candidates.
It will set out minimum standards of behaviour expected from all political party members, the foundation said, adding it hopes to reach an agreement before any upcoming general election.
The foundation added intimidation was a "cross-party issue" which poses a threat to the "diversity, integrity, and vibrancy of representative democracy" in the UK.
Speaking to BBC Radio 4's Today programme the day after the Commons debate, Mr Cox urged all sides to moderate their language.
He said: "There is a willingness to jump out and decry the other side when they use language like 'surrender' or 'traitor' or 'betrayal'.
"And I think that is inflammatory language, but I think as inflammatory are those people who have used the language of it being a 'coup' and a 'dictatorship'.
"I think both of those approaches are unacceptable."
The foundation said the code will actively promote and support the seven Nolan Principles of Public Life, which form the basis of the ethical standards expected of public officials - selflessness, integrity, objectivity, accountability, openness, honesty and leadership.
The code has been developed using recommendations made in the CSPL's 2017 report on intimidation in public life and a review of existing internal party codes, it added.
CSPL chairman Lord Evans said he was "delighted" by the progress in tackling intimidation, adding: "Standards in public life have rarely been more in the spotlight than they are today."
Catherine Anderson, chief executive of The Jo Cox Foundation, said Mrs Cox's murder was a constant reminder that the threat of violence and intimidation towards MPs, candidates or anybody else in public life can never be acceptable.
"We all value vigorous political debate and freedom of speech but that should not extend to abusive behaviour designed to intimidate and silence people. It threatens our democracy itself," she said.