An anti-tax group lashed out at Gov. Charlie Baker on Tuesday, calling the Republican governor “a disappointment” after he rolled out a plan last week to generate about $1 billion over the next decade by hiking the excise tax paid on real estate transfers.

Citizens for Limited Taxation blasted Baker’s proposal to increase the real estate transfer tax to fund a program that will help cities and towns deal with the effects of climate change as a “scheme” and an “assault on taxpayers.”

Baker on Friday announced a proposal to raise the excise rate from $2 per $500 of assessed value to $3 per $500 of value, saying it represents “a point-two percent increase.” The governor said his plan, which he said is designed to generate $137 million annually for climate adaptation projects, will be a good value for taxpayers and residents.

“This is an excise tax that’s basically about property and the proposal we’re making here is to protect property,” he said Friday. “We think, in the long run, the cost/benefit on this one is a good deal for Massachusetts residents.”

CLT on Tuesday called that comment from the governor “a lame defense of this latest breach of trust” and slammed him for the tax increases he’s previously approved, like new assessments on the health care industry and taxes on short-term rentals. The Republican governor has touted his general opposition to new taxes and fees, but in just the last roughly 10 days he has proposed taxing daily fantasy sports, legalizing and taxing sports wagering, and increasing the tax on real estate transactions.

Baker “has an excuse for every betrayal. He’s smooth, he’s slippery, and he’s sliding down the slope, seemingly a victim of Stockholm syndrome,” CLT said in a statement. “For a candidate who campaigned on opposition to raising taxes and fees, Gov. Baker has become – well, a disappointment.”

As a candidate for governor in 2013, Baker said he is “a reform before revenue guy and I’m going to be the taxpayers’ best friend on that whole question.”