No Government can introduce a new national pension scheme without agreement in principle from the opposition parties. Otherwise the scheme won’t last beyond the next change of Government. But the Conservatives have warned this week that they will vote against plans for a new semi-compulsory pension for everyone in work unless the Government makes one key concession. So far there is no sign that it will.

The Bill to introduce the new Personal Accounts – which is a daft name for a pension scheme and let’s hope the Government changes it as the Bill goes through Parliament – was announced in the Queen’s Speech this week.

When the new scheme starts in April 2012 every employer will have to pay into a pension for their workers. At the moment many employers do not have a scheme in place leaving millions with nothing apart from the state pension to support their retirement. The minimum contribution into personal accounts will be 5% of pay by the employee and 3% by the employer though both will get tax relief to reduce that cost.

Every employee will have the right to opt out of the scheme if they choose. But the decision about whether it is worth paying in or not will be a difficult one.

One of the main concerns is that some people on low incomes or who are close to pension age will not pay enough into the scheme to earn a pension that is big enough to lift them off means-tested benefits. On the Government’s own figures one in three pensioners will still be entitled to the means-tested Pension Credit when the new system is fully up and running.

Conservative Shadow Pensions Secretary Chris Grayling told the Financial Times this week that he will vote against the plans unless the key issue of means-testing is dealt with.

With the next General Election due at least two years before the new scheme is due to start such threats have to be taken seriously. But so far no clear and costed alternative has come from the Conservatives.

Abolishing means-testing would involve raising the state pension by about £37 a week to the same level as Pension Credit and would cost £14 billion a year. One alternative would be to refund any contributions made if it turned out that an individual had not benefited from paying in. But that would be expensive too. Liberal Democrats have also indicated their opposition to elements in the new plans.

But one way or another a consensus has to be found. Or the whole ten year process of pension reform will have to be started again. And no one wants that.