I'm in charge, says Clegg, as PM goes to the seaside

A year ago it would have been considered a pipe-dream for all but the most incurable of Liberal Democrat romantics. Their leader will return from his Spanish holiday tomorrow to take charge of Britain for the next fortnight.

David Cameron will remain in overall control during his family break in Cornwall, but officials have been told only to bother him on the most pressing issues, leaving the Deputy Prime Minister responsible for the daily business of government for two weeks – the first time a Liberal has run the country since David Lloyd George in 1922.

Nick Clegg has spent just over two weeks in the central Spanish province of Castile and León, where his wife, Miriam, was brought up. Each year the couple take their children to stay with his in-laws.

Colleagues say Mr Clegg, who this week endured the indignity of a newspaper photograph of him on holiday looking paunchy, is returning to work feeling "refreshed and upbeat".

Mr Cameron is heading for Cornwall. Last August he went to Brittany and Greece, but this year has chosen a domestic location in an effort to bang the drum for British tourism. Staying in this country will also suit his heavily pregnant wife, Samantha.

Mr Clegg will follow the Prime Minister's lead in holding a series of meet-the-people events in which he sets out the coalition's agenda. As well as defending its austerity measures, he plans to offer a more positive vision of its ambitions for the next five years.

On Wednesday, his 100th day in office, he will use a major speech to stress his commitment to increase social mobility. The following day during a visit to the North-east, he will turn to another of his key themes, the need to boost economic growth in the English regions.

Both Tory and Liberal Democrat officials are anxious to avoid a repeat of the Blair and Brown years, when deputies attempted to make their mark while the boss was out of the country. But Mr Clegg, who will undertake a series of television interviews, will also be keen to demonstrate to worried party activists that he is helping to dictate the coalition's priorities.

He will also want to banish memories of an uncomfortable appearance last month at Prime Minister's Question Time, when he deputised for Mr Cameron, who was in the United States.

Mr Clegg will also be aware of jitters among his MPs and activists over the party's plunging opinion poll ratings in the last two months. A ComRes poll for The Independent this week put the party on 16 per cent support – down six points since the election – and found that more than one in three Liberal Democrat voters on 6 May had turned their back on the party.

Mr Clegg will argue that the party has been used to highs and lows in the polls but will ultimately recover support.

When the PM's away...

August 1997

John Prescott, when he was Deputy Prime Minister, mocked his cabinet colleague Peter Mandelson during a photocall on the Thames by likening him to a crab while the Prime Minister, Tony Blair, was on holiday.

May 2006

Mr Prescott is photographed playing croquet at his official residence, Dorneywood, while Mr Blair was attending a summit in the US.

August 2009

While Gordon Brown was away on holiday Harriet Harman caused some angst in Downing Street when she blamed the male dominance of the banking sector for the global financial crisis.

August 2009

For three days the country was run from a Corfu villa by Lord Mandelson. An aide explained he was in contact with London by BlackBerry.