German Chancellor Angela Merkel's conservatives have agreed plans to introduce a mandatory minimum wage for sectors of the economy that do not already have one, in the latest policy shift to try to win over left-leaning voters.

Merkel's Christian Democrats (CDU) have long opposed a blanket minimum wage, arguing that it would amount to excessive political interference in the wage-bargaining process between workers and employers.

But the CDU came out in favour at a party congress late last year and, after talks with its Bavarian sister party, the Christian Social Union (CSU), agreed a blueprint on Wednesday that was unveiled by Labour Minister Ursula von der Leyen.

According to the plans, a non-partisan committee of employers and employees would be set up to fix a nationwide minimum wage and monitor it annually. Industries that already have a minimum wage would not be affected by the new national measure.

We want fair wages in Germany and an across-the-board minimum wage, CDU lawmaker Peter Weiss, who took part in the talks, said.

The CDU and CSU will now open negotiations with their junior coalition partner, the Free Democrats (FDP), with a view to putting together a draft law later this year.

The business-friendly FDP is generally opposed to the idea of a minimum wage, but even if Merkel cannot convince them, her attempt to introduce it could help neutralise what is expected to be one of the opposition Social Democrats' (SPD) main campaign themes in next year's federal election.

The minimum wage reversal is the latest example of Merkel co-opting the policies of the centre-left SPD and Greens to bolster her own party's attractiveness to centrist voters.

Since first coming to power in 2005, she has pushed her party to focus on environmental, education and childcare policy, traditional domains of the left.

Last year, in her biggest and most sudden policy shift, she dropped her longstanding support for nuclear power following the Fukushima disaster in Japan, shutting down over half a dozen older German plants and accelerating a nationwide phase-out plan.

Although German unemployment is at its lowest level since reunification in 1990, data from the German Labour Office shows that the low wage sector grew three times as fast as other employment during Merkel's first five years in power.

This has left her vulnerable to accusations that some Germans have not fully benefited from the strength of Europe's largest economy.

Germany has long had minimum wages in place in specific industrial sectors, but not a national measure, as exists in many other western countries like the United States or France.

In a paper unveiled at their party congress in Leipzig last year, the CDU said the level of a new minimum wage should be in line with what is already in place for part-time workers -- 7.79 euros per hour in western Germany and 6.89 euros in the east.

(Reporting by Noah Barkin and Holger Hansen; Writing by Noah Barkin; Edited by Stephen Brown)