Shadow chancellor John McDonnell said this morning Labour will shift the tax burden to those earning "£70,000 to £80,000" if it wins the election.
Speaking on the BBC's Today Programme, McDonnell said Labour wanted to ensure a "fair taxation system".
"You'll see that the burden in terms of the tax take has fallen on middle and low earners, people below the higher tax bands," he said.
"We'll be looking to the corporations and the rich to pay their share... we believe the rich [are those earning above] £70,000 to £80,000 per year."
McDonnell also said Labour would have waited until after a Brexit deal had been agreed to call an election.
"The Prime Minister has a mandate to go off and do the negotiations," he said.
"[But] you'd expect the government would then come back, put the deal to Parliament and [then] possibly the country overall.
"When a deal is agreed it can be put to Parliament. That's when you'd call a general election."
Although figures have suggested Labour will lose 48 seats in June's vote, McDonnell said the party will back the snap Election in today's parliamentary vote.
"This will give [people] the opportunity of deciding whether they want a Conservative or Labour government. People should have that right we're not going to stand in the way of that," he said.
"We see this as an opportunity for removing a Tory government and replacing it with a Labour government."