Plaid Cymru's leader is expected to tell his party that only it can secure "the best possible deal for Wales" in the event of a hung parliament.
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 will argue the "most likely" outcome of a general election, "and the best outcome for Wales", would leave no party with overall control.
Ieuan Wyn Jones told the party's conference they were aiming to increase the number of MPs from three to five.
At his party's conference in Cardiff he will outline the demands Plaid would put to a prospective UK government.
He told delegates in Cardiff that his MPs would fight to protect public spending in Wales after the election.
He is likely to say their delivery would be the price of Plaid support.
He said the public no longer had confidence in either the Labour or Conservative parties.
At the top of such a list would be a demand for Wales to get what Mr Jones calls "its fair share of funding... so that we can protect our schools and hospitals from the cuts in public spending".
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".
Mr Jones will argue that there is no point voting for Welsh Labour and Conservative MPs in the expectation they'll stand up for the needs of Wales.
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".
He will say that such MPs always "toe the party line" and put the party political interests of "their masters in London before the interests of Wales".
Sir Jon had argued against relative cuts to the Welsh assembly government's budget.
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 Ieuan Wyn Jones, Plaid Cymru leader
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.
Mr Jones is also expected to outline how he would call for the immediate introduction of redistributive tax measures to help pensioners and those on low incomes to escape poverty.
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".
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...
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."
"We want to make sure that the next parliament understands the needs of Wales."
Mr Jones will argue that Plaid's focus for the election will also be on building a stronger, more resilient and sustainable Welsh economy.
Venture capital fund
He has called for a new venture capital fund to be established by the Treasury, to benefit companies which are unable to secure funding.
The fund, set up by government jointly with approved private sector organisations, would either provide loans or funding secured by taking an equity share in companies.
Mr Jones called for the Treasury to set up a UK-wide fund - a proportion of which would be made available to the Welsh Assembly Government.
He said: "We've now really got to support businesses coming out of the recession, moving into the growth mode.
"We want to make sure that they have sufficient resources to enable them to do that and of course that's why we're launching our venture capital fund which will assist companies to develop, having the kind of capital that's not really been available, historically, in Wales."
Plaid Cymru conference programmes will be on Saturday, on S4C from 0955 - 1155 GMT, and on BBC 2 Wales from 1415 -1615 GMT.
Plaid Cymru conference programmes will be on Saturday, on S4C from 0955 - 1155 GMT, and on BBC 2 Wales from 1415 -1615 GMT.
