Irish prime minister Leo Varadkar warned that Johnson looked to be embarked on a "harder Brexit than we anticipated" and said he feared the UK wanted to "undercut" Europe on food, health and product safety after it exits.
Conservative Party leader Boris Johnson told MPs on Friday that the "oven was on" when it came to delivering Brexit next year but said there would be "no alignment" to EU rules once the transition period ends in 2020.
He said: "The Bill ensures that the implementation period must end on December 31 next year, with no possibility of an extension, and it paves the way for a new agreement on our future relationship with our European neighbours, based on an ambitious free trade agreement.
"This will be with no alignment on EU rules, but instead with control of our own laws, and close and friendly relations."
Charles Michel, the successor to Donald Tusk as European Council President, welcomed the Commons result but suggested in a tweet that "a level playing field remains a must for any future relationship".
Taoiseach Varadkar warned a "good trade deal" for Ireland was looking increasingly unlikely after the stance taken by Number 10 since the Tories' thumping General Election win.
"It is going to be difficult to secure a good trade deal for Ireland, principally because Boris Johnson has fixed on a harder Brexit than we anticipated under his predecessor or at the time of the referendum, and that is one where he talks very much about divergence," he told journalists in Dublin.
"The harder approach being taken by prime minister Johnson is a risk to us and that is evident."
Varadkar said he feared the UK, under a hard Brexit, would look to "undercut" EU member states on food, financial, product and health standards in order to compete for world trade.
