The government should set a target date for "everybody in the country" to speak English to encourage integration, a former official has said.
Dame Louise Casey, who wrote a report for the government on integration in 2016, said a "common language" would help to "heal rifts across Britain".
She also called for further work on gaining equality for women, and the "white working class population".
The Integrated Communities Strategy is due to be published later this week.
In her 2016 report, Dame Louise recommended providing additional funding for local government to promote English language skills, including prioritising adult skills budgets and providing community-based classes.
But she has criticised the government for not taking any action since its publication.
'Speak one language'
Speaking on BBC Radio 4's Westminster Hour, Dame Louise said that integration should be "one of the most significant priorities" for the government and that any more delays to the strategy would be "incredibly frustrating".
She called for "big, bold policies" to tackling issues around integration, including a "very significant boost" in promoting the English language.
Dame Louise said: "I would be quite old school about this and I would set a target that says by 'x' date we want everybody in the country to be able to speak a common language."
She added: "I don't care how we've got here, I don't care who can't speak English [and] I don't care what's going on.
"But what I do know is everybody of working age and of school age should be able to speak one language and I think the public in particular would feel some relief."
She also called for "social-economic splits" to be addressed in the strategy, which she pointed to in her own report.
"I think parts of the North, where we've got a very significant white working class population who feel incredibly alienated, who do not have, frankly, hope... they can't say that their kids will grow up [with] better lives than they have themselves," she said.
"It's not only about the tides of immigration and migration and English language, but some of this is about equalities for women, as well as equalities overall, as well as in terms of social and economic disadvantage.
"Let's see what they come up with."
Conservative MP and former immigration minister Mark Harper said the government had made changes to immigration rules to require a "better level of the English language" when people came into the UK
But he welcomed Dame Louise's recommendations and acknowledged there were concerns about areas of the UK where people cannot speak the language.
He told Westminster Hour: "I think the recommendations she has made are very powerful and I hope the government produces an ambitious strategy."