Lord Carlile expressed doubts about the timing of any return

In July, South Wales Police launched a probe into alleged fraud at the European unit of the Welsh Joint Education Committee, formerly headed by the assembly member.

He has stepped away from the coalition cabinet and the role of Economic Development Minister for the duration of the investigations.

But now, the police force has said its investigation has some months left to run and the respected former Liberal Democrat has expressed doubts about Mr German's return.

'Continuity lost'

Lord Carlile told BBC Wales's Dragon's Eye: "It's certainly feasible for Mike German to return to the cabinet, if that's thought appropriate, once the inquiry has concluded - provided, as one hopes, the conclusion is favourable to him.

"But we don't know when that's going to be and I think it's likely that the election is going to be so close, when the inquiry is concluded, that continuity will be lost."

I think he should be looking to appoint someone into the economic development portfolio as soon as he is able to do so

Tom Middlehurst, Labour AM

Lord Carlile had earlier called on Mr German to step aside from his deputy first minister position.

Days later, he took the decision to temporarily walk away from that position, which has been taken care of by fellow Liberal Democrat Jenny Randerson.

It was First Minister Rhodri Morgan, however, who took the economic development portfolio, and now a Labour colleague urged his leader to make a new appointment.

'New appointment'

Alyn and Deeside AM Tom Middlehurst said: "By the end of this session, if the issues surrounding Mike German are not resolved - and the signs are that it's going to be a long-running affair, well into the New Year - I don't think that's sustainable.

"I think he should be looking to appoint someone into the economic development portfolio as soon as he is able to do so."

The first minister is also economic development minister

But Mr Morgan rejected that call from opposition members in the assembly chamber earlier in the week.

In response to Conservative assembly leader Nick Bourne, the first minister said: "Where are the delays that have been caused by the administration having a first minister who shares the post of economic development minister?"

Mr German has always maintained the inquiries will clear him of any wrongdoing, allowing him to step back into his jobs.

He has argued he is the victim of a political witch hunt by opponents of the Lib-Lab coalition government in Cardiff Bay.