He said it was the duty of a “healthy opposition” to hold the Government’s “feet to the fire” after the Prime Minister cited “division” in Westminster over Brexit for calling the election.
The former Deputy Prime Minister accused the Tory leader of wanting to “arrogate herself extraordinary amounts of power” by increasing her majority in the House of Commons.
Mr Clegg told BBC News: “I fundamentally disagree with it as a matter of democratic principle.
“Healthy opposition, holding the powerful – their feet to the fire – is an essential ingredient to our democracy and in effect what she wants to do by opportunistically calling this election to exploit the weaknesses of Jeremy Corbyn is to arrogate herself extraordinary amounts of power.
Nick Clegg bashed Theresa May and claimed she wanted more power
I only splutter with indignation because it is such a ludicrously confected fake reason
“And I think nobody who cares about the quality of our venerable democratic tradition should be relaxed about that.”
When asked about the Lib Dems, SNP and Labour criticising the Government at every stage despite Brexit voters wanting the Prime Minister to “get on with it”, Mr Clegg snapped back.
He interrupted: “Who’s stopping her? No one’s stopping her!”
The host replied: “She says your party’s stopping her, the SNP is stopping her and Labour is slowing her down.”
Politicians react to Theresa May's snap general election Wed, April 19, 2017
UK Prime Minister Theresa May has announced her intention to hold an early general election on June 8
EPA 1 of 10
Get Quotes on Home Insurance
Theresa May has called for a snap general election
Mr Clegg said the Prime Minister was "exploiting the weaknesses of Jeremy Corbyn"
Mr Clegg hit back and said: “Sorry to interrupt, I only splutter with indignation because it is such a ludicrously confected fake reason.”
The comments come as Nicola Sturgeon opened the door to a left-wing pact to stop Mrs May from returning to Number 10.
The SNP leader said her party would seek to form a "progressive alliance" with Labour and the Liberal Democrats after the snap General Election.
But she conceded that, unlike 2015, when she proposed a similar deal there was no prospect of Jeremy Corbyn's party winning enough seats to keep the Tories out.
The First Minister speaking on a visit to her MPs outside Parliament, said: "If the Parliamentary arithmetic lends itself to the SNP being part of a progressive alliance to keep the Tories out of Government then the SNP will seek to be part of that as we said in 2015.”