Reform UK has threatened to review and potentially remove all government contracts held by outsourcing giant Serco if the company refuses to support the party's proposed mass deportation programme for illegal migrants.
The dispute follows reports in The Telegraph that Serco had ruled out involvement in a US-style Immigration and Customs Enforcement (ICE) campaign under a future Reform government.
In a letter to Serco chief executive Anthony Kirby, Reform's home affairs spokesman Zia Yusuf warned: "If this were true, I am sure you appreciate a Reform government would be left with no choice but to view Serco as a threat to national security."
He added: "I would understand if Serco refused to engage in partisan politics and maximised shareholder value ... However, we will not accept Serco or its representatives taking political positions as it suits you."
Mr Yusuf also criticised Serco's role in managing asylum-seeker accommodation, describing it as "morally repugnant", and gave the company until Tuesday evening to clarify its position.
Responding, Mr Kirby insisted Serco remained politically neutral. He said: "As a matter of longstanding company policy, Serco does not take political positions, nor do we comment on the policy programmes of political parties."
He added: "Policy decisions are matters for whatever party is in government. Serco's responsibility is to deliver services as specified by the contracting authority as we have for the past 60 years."
Reform's proposed immigration policy, dubbed "Operation Restoring Justice", aims to deport up to 600,000 illegal migrants over five years and would require significant support from private-sector contractors operating across the immigration system.
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