MPs are being asked to approve more money for the "stabilization" of the government's problem-plagued electronic pay system — including a $14 million loan for the unions representing civil servants.

At the same time, government employees are being warned not to overload government computers with requests for the T4 slips they'll need to file their 2017 tax returns.

Spending estimates tabled earlier this week in the House of Commons tally the additional expenses related to the Phoenix system at about $186 million, most of which is earmarked for hiring new pay advisers.

However, only about $76.3 million of that is new spending, say officials with Public Services and Procurement Canada, which oversees the pay system.

Of that amount, $56.4 million would be spent essentially hiring new people and buying computers and software, officials said.

If approved by Parliament, the new funding will bring the total cost for Phoenix to nearly $788 million, including the initial $309 million used to set up the troubled system and $402 million the government announced last May that it needed to bring the Phoenix system to a so-called "steady state."