Ieuan Wyn Jones said his party would demand fair funding for Wales
Plaid Cymru's leader has told his party that a hung parliament is likely after the general election and would be the "best outcome" for Wales.
Ieuan Wyn Jones told the party's conference they were aiming to increase the number of MPs from three to five.
He told delegates in Cardiff that his MPs would fight to protect public spending in Wales after the election.
He said the public no longer had confidence in either the Labour or Conservative parties.
"For the first time in a generation, we could see a hung parliament following the election in May," he told the conference.
"It means that the public no longer have confidence in the two main parties in Westminster.
"It means that the time for politics as usual is over, and it means that the time is ripe to elect Plaid Cymru MPs who will secure the best possible deal for Wales".
'Accepting there is problem'
Mr Jones told the conference that Plaid would demand "fair funding" for Wales "so we can protect our schools and hospitals from the cuts in public spending".
He quoted Wales' former top civil servant, Sir Jon Shortridge, who had suggested the nation's relative poverty could be due to being "governed from England for too long".
Sir Jon had argued against relative cuts to the Welsh assembly government's budget.
Mr Jones also said there was no point voting for Labour and Tory candidates in the expectation that they would stand up for the needs of Wales.
He said MPs from the two main parties always "toe the party line" and put the party political interests of "their masters in London before the interests of Wales".
He added that Labour and the Conservatives in Wales accept there is a problem with the funding formula for Wales
"But what is the point of accepting there is problem, if they're not willing to do anything about it."
Earlier, Mr Jones told BBC Wales: "What we want to do is to make it absolutely clear that we are a serious party, a party of government in Wales, therefore we are taking this general election which we're facing very seriously indeed.
"We want to make sure that the next parliament understands the needs of Wales."
Plaid Cymru conference programmes will be on Saturday, on S4C from 0955 - 1155 GMT, and on BBC 2 Wales from 1415 -1615 GMT.