The BBC's coverage of the General Election could be hit if workers at technology partner Siemens vote for industrial action.
Although the BBC has been assured by Siemens that potential action will not disrupt its broadcasting, union Bectu has pledged to time any strike to maximise its impact.
A 24-hour strike of IT workers could be on the cards as early as 29 March, after Bectu balloted members working for Siemens at the BBC. The move follows redundancies, a pay freeze and servers possibly being outsourced to Romania.
The ballot will close on 19 March and notice will have to be given for strike action.
Bectu national officer Suresh Chawla said action could be taken anytime after 29 March, if members vote yes. He said in an attempt to maximise the impact of any action, the BBC's coverage of the General Election build up could be hit.
"We are recommending that members accept industrial action," said Chawla.
As well as a one-day general walkout, action could include strikes in key job roles on specific days.
In 2005, Siemens took over the IT at the BBC in an outsourcing deal that saw the BBC sell off parts of its IT operations. About 1,400 BBC workers transferred to Siemens under the deal. Siemens has since made 70 people redundant and there are plans to outsource server operations to Romania, which would lead to more cuts.
Chawla said Siemens had planned to send server operations to India but was not allowed to because of data protection concerns. "But Romania is in Europe, so it can send the data there. It is also a lot cheaper than the UK," he said.
The BBC said it has been assured by Siemens that its business will not be disrupted by any strike action. "As the BBC's technology partner, Siemens is responsible for keeping our services on air and online. They have kept us informed as talks have progressed and assured us that, in the event of strike action, contingency plans are in place to ensure there will be no adverse effect on audiences," said the BBC.
Siemens said, "Like many other organisations, Siemens is not awarding company-wide increases in pay this year, and this reflects the current market conditions. We are disappointed that Bectu has chosen to conduct a ballot for industrial action as we believe that any industrial action will not be in the interests of our employees or customers. We therefore remain hopeful that a negotiated settlement can be reached."