BERLIN, March 5 (Reuters) - The German government will introduce an additional pension scheme investing in capital markets to ensure that pensions remain linked to wage trends, a draft of the new law seen by Reuters on Tuesday showed.

Due to demographic developments, Germany's pension system is coming under increasing pressure, as the gap between salaries and pensions is growing.

The aim of the reform is to guarantee a pension level of at least 48% of an average wage until the end of the 2030s. This will allow pensioners to maintain their living standards after retirement.

To relieve the burden on contributors in the long term, a permanent capital stock will be built up with loans from the federal budget and transfers of government funds.

As a first step, the government wants to take 12.5 billion euros ($13.56 billion) in debt this year for the so-called Generational Capital, in order to invest in capital markets.

A capital stock of 200 billion euros is to be accumulated from federal debts by 2036. The returns are to enable annual distributions to the pension insurance scheme of 10 billion euros by investing in shares and funds.

A security buffer for distributions is set up to protect the assets, in particular the loan amount granted.

Contributions to the pension system have been stable at 18.6% since 2018 and will remain at this level until 2027, according to the ministry.

From 2028 contributions will increase to 20% and from 2035 to 22.3%, which will then remain stable until 2045, according to the ministry's estimates.

($1 = 0.9219 euros) (Reporting by Maria Martinez; editing by David Evans)