Including the pledges in the manifesto would make it extremely hard for Remain-backing Tory MPs to rebel on the issues in House of Commons votes if the party wins the snap election on June 8 and as exit talks go on.
It had been hoped talks could start by the end of that month, but EU Commission spokesman Margaritis Schinas said Wednesday that "the real political negotiations" with Britain would not start till after the June 8 election.
Lawmakers in the House of Commons voted 522 to 13 on Wednesday to support the motion put forward by May a day earlier.
Because she was not leading the Conservative Party at the time of the last general election, she has no personal mandate as leader.
The former Belgian prime minister said, "The UK election is an internal affair, but clearly Brexit will be the key element of it".
He spoke in defence of ordinary people who he said spent their lives working hard and in the end were left with nearly nothing.
Britain will go to the polls on June 8, after MPs cleared the way for an early general election.
In his first major general election speech, Jeremy Corbyn has attempted to frame the upcoming contest as a battle between "the people" and "the establishment".
Instead, the British chose to leave in a vote that has roiled British politics ever since, starting with Cameron's resignation.
"We've set out our lines on negotiation".
While she tries to focus the debate on Brexit, Corbyn is looking to harness a powerful anti-establishment mood revealed by last year's European Union referendum and echoed in the rhetoric of Bernie Sanders and Donald Trump during last year's USA election campaign.
Conservative Party chairman Sir Patrick McLoughlin then seized on the comments, insisting Mr Corbyn was sowing "chaos" which would "disrupt our Brexit negotiations".
The Lib Dem leader predicted that Labour will lose "dozens and dozens" of seats on June 8, and said that the only threat to Conservative MPs came from his party.
Mrs May, who became PM last July after the European Union referendum, told MPs it would wrong for the United Kingdom to find itself reaching the most "difficult and sensitive" phase of Brexit negotiations in late 2018 and early 2019 when a general election was "looming on the horizon".
A debate would also see May challenged over her handling of Brexit, where she has steadfastly refused to share even the slightest shadow of her plans with the country or parliament until she was forced to by the courts.
If the election is approved today, Parliament will be dissolved on May 2, sparking nearly six weeks of campaigning.
When asked who they thought would make the best Prime Minister, 54 per cent backed Theresa May, with just 15 per cent saying that Jeremy Corbyn would make the best leader.
Fellow South East MEP Keith Taylor, of the Green Party, said the vote was the equivalent to a second referendum on Brexit.
Corbyn, whose deeply divided party is languishing behind the Conservatives in opinion polls, accused the government of "broken promises" on health, education and the economy during its seven years in office.