The move follows a ruling by the European Court of Human Rights (ECHR) in November 2012, that UK law does not give adequate protection to employees, including members of the British National Party, who could be dismissed because of their political affiliations.
Ministers will exempt those claiming they were axed because of their political beliefs from rules which require workers in the UK to have been in a job for two years before they can claim unfair dismissal.
The law change, which is unlikely to be opposed, will be debated in the House of Lords on 26 February when the Enterprise and Regulatory Reform Bill reaches its report stage.
Naeema Choudry, partner at global law firm Eversheds, said: "The change will mean that all employees will be able to challenge politically motivated dismissals, regardless of their length of service.
"This does not mean that it will never be appropriate to dismiss somebody because they are a member of a political party; it simply means that employees will be able to have a tribunal look into the decision to dismiss and decide whether it was reasonable.
"Whether a dismissal is reasonable or not will, to a large extent, depend on the nature of the individual's job and, in some cases, the area in which they work.
"An employer will be on firmer ground if membership of certain organisations is incompatible with the individual's job and there is a clear policy spelling this out.
"It is possible too that an organisation with an ethos that is demonstrably based on strong ideological views on social or political issues might be able to justify dismissal of someone whose political affiliations run contrary to that ethos."
She added: "However, a mere desire to avoid any adverse publicity or embarrassment that may result if an employee's political leanings are made public is less likely to stand up to scrutiny."
Business minister Viscount Younger of Leckie said: "This amendment exempts claimants who allege that their dismissal was on the grounds of political opinion or affiliation from the two-year qualifying period," he told Parliament in a written ministerial statement.
