Wales' First Minister Carwyn Jones has criticised the decision to call a general election in the middle of a council election campaign.
Prime Minister Theresa May announced an early election for 8 June, saying it was the only way to guarantee stability after the Brexit vote.
Mr Jones said the election was "not in the national interest".
But Welsh Secretary Alun Cairns said UK ministers were in the position 'reluctantly'.
Welsh Tory leader Andrew RT Davies said the decision was right, while Plaid Cymru leader Leanne Wood tweeted: "Game on."
Mrs May's decision was taken during a walking holiday in Snowdonia with husband Philip.
Mr Jones reacted to the announcement first on Twitter, tweeting: "Calling an election in the middle of another election is odd. Northern Ireland peace process high and dry?
He later added: "I have to say though that this election isn't in the 'national interest'. Focus should be on Brexit and the economy not opinion polls".
"We won last year's assembly election based on our strong record of leadership and delivery," Mr Jones later said.
"We will enter the general election campaign, whenever it comes, from a position of strength and with a distinctive and innovative offer for the people of Wales."
Shadow Welsh Secretary, Labour Neath MP Christina Rees, said "Labour will be offering the country an effective alternative to a failing Tory Government at Westminster".
Tory Welsh Secretary Alun Cairns said: "We're in this position reluctantly.
"We've seen that the opposition parties are using the parliamentary process to frustrate the Brexit negotiations, and leaving the prime minister potentially in a weaker position to negotiate with the European Union.
"This will strengthen the government's hand to get the right deal for Wales."
Welsh Conservative leader Andrew RT Davies said the snap election was "the right decision for the country".
"Here in Wales, both Labour and the Welsh nationalists have been in denial over Brexit, and have sought to undermine the process at every stage," he added.
He said every vote for the prime minister on 8 June "will strengthen Britain's hand in the negotiations ahead".
Plaid Cymru leader Leanne Wood said: "Plaid Cymru is united and we're up for the opportunity to advocate for Wales' best interests.
"The more Plaid Cymru MPs, the stronger Wales' voice will be."
A spokeswoman for Plaid Cymru said Ms Wood had not ruled in or out standing in the Rhondda constituency.
Welsh Liberal Democrat leader Mark Williams, MP for Ceredigion, said the poll was a "chance to change the direction of the country".
"If you want a Britain that is open, tolerant and united, this is your chance," he said.
Senior Welsh Conservative MP David Davies welcomed the announcement, telling BBC Wales: "A strong victory will help us achieve what we want to achieve in our negotiations with the EU."
Leader of UKIP in the assembly, Neil Hamilton, "welcomes the news of a snap general election".
"This is a great opportunity for the electorate to vote out those remain MPs in Wales and elect a UKIP MP who will represent their interests in parliament," a UKIP spokesman in Wales said.
He told BBC Wiltshire his party "will have a candidate in every single constituency" across England and Wales.
Analysis by BBC Welsh affairs editor Vaughan Roderick
Wales will be heading to the polls for the fifth time in two years in June and all the political parties will have to scramble to select candidates and draw up manifestos and strategies for an unexpected contest.
Following a strong showing in Wales in 2015, the Conservatives face a shortage of obvious target seats, although party strategists will hope seats like Wrexham, Clwyd South and Newport West could come into play if the party's current lead in the polls holds up.
Unless Labour's fortunes revive, the party is likely to find itself on the defensive in Cardiff Central and Ynys Mon, where the Liberal Democrats and Plaid Cymru will try to cash in on Labour's current difficulties.
Before engaging in the Westminster contest though, there's the little matter of the local elections on 4 May to deal with.
National politics always has an impact on the council results and that influence can only increase given the imminence of a general election.