Senior Liberal Democrat Ed Davey has revealed he would like to lead the party if Nick Clegg “hangs up his clogs” after the next election.

The energy and climate change secretary signalled he would probably throw his hat into the ring if a vacancy for Lib Dem leader arises, but said it was most likely that this was some years away.

In an interview with LBC 97.3, Davey said: “If it turns out when Nick Clegg hangs up his clogs as leader … whether that’s directly after the next election – I doubt it – or in a few year’s time – more likely – when he does that, of course there will be colleagues like myself and others, who will think about whether they want to stand for leader. That’s not unreasonable.”

He added: “If one day it falls to me to lead it, then obviously, I’d like to do that.”

His comments are likely to be seen as positioning himself as a contender in the event of the Lib Dems suffering a devastating loss of MPs at the election. Danny Alexander, the chief secretary to the Treasury, has previously hinted he could be a candidate, saying that was a “decision that will be made”.

One poll this week showed them with lower national support than the Green party, but the Lib Dems argue they have a good chance of holding in their traditional strongholds, where their local activists and MPs are dug in. Davey said he is still optimistic about his party’s chances at the next election and thinks they will be a surprise success story of the election.

He spoke as the Lib Dems prepare to publish their line-up of departmental spokespeople ahead of the election, which will confirm Alexander has the economic portfolio instead of Vince Cable, the business secretary.

Tim Farron, the former party president, who is considered on the left of the party, is expected to get the foreign affairs brief, while former Scottish secretary Michael Moore is likely to get the Europe portfolio.