LONDON (Reuters) - Britain's parties should step away from "tawdry political tactics" that are unsettling investors before a 2015 election and focus instead on spelling out long-terms plans for the economy, a business lobby group said on Monday.
The outcome of May's vote is uncertain with the center-left opposition Labour party holding only a slim lead over Prime Minister David Cameron's Conservatives. The rising popularity of nationalist and single-issue parties is also likely to complicate the result.
Cameron has promised a referendum on whether Britain should stay in the European Union if he wins, worrying some businesses. Some also fear a Labour victory could bring in a new era of tighter regulation.
Against that backdrop, the British Chambers of Commerce (BCC) said the election was causing huge nervousness among businesses.
"For many businesses, both small and large, one of the greatest sources of challenge and uncertainty in 2015 isn't the state of global markets, but home-grown politics," BCC Director General John Longworth said in an open letter to leaders of 12 political parties.
Longworth said political parties needed to set out long term policies on public spending, taxation and education to give firms the confidence to invest, hire new workers and take risks in export markets.
The Conservatives have raised the possibility that Britain could withdraw from the EU by promising to hold a membership referendum by 2017, in a bid to stop voters defecting to the anti-EU UK Independence Party (UKIP).
Labour have appealed to voters who have seen their living standards squeezed by stagnant wages and rising prices by calling for tighter regulation in industries ranging from banking to energy.
The BCC represents businesses employing more than 5 million people across the country.
(Reporting by William James; Editing by Andrew Heavens)