The £300m acquisition from Trinity Mirror had been referred to the Competition Commission in March under standard newspaper merger rules.
Trinity Mirror was required to sell the group, which includes The Belfast Telegraph, as a pre-condition of its takeover of Mirror Group last year, which already owned a number of Northern Irish titles.
The Belfast Telegraph is the biggest-selling paper in the region with a daily circulation of about 117,000. Other publications in the group include the Sunday Life, Farm Telegraph and Community Mirror.
The acquisition by Independent News and Media, which holds the Independent newspaper and the Dublin-based Irish Independent among its portfolio, had raised concerns among unionists.
Worries over jobs
They feared IN&M would have had a majority of local paper ownership both north and south of the Irish border.
There were also worries the sale would lead to jobs being cut in Northern Ireland if printing presses and advertising teams were moved to the Republic of Ireland.
But the commission found little evidence of competition between daily newspapers north and south of the border and little cross-border advertising.
It also reassured unionists that the papers would still need to be printed in Northern Ireland, thus safeguarding jobs in the region.
Stephen Byers, Secretary of State for Trade and Industry, said: "The Competition Commission has considered thoroughly the effects of the transfers on the accurate presentation of news and free expression of opinion, concentration of ownership, prices, quality, consumer choice, efficiency and employment."
He said: "I accept its unanimous conclusion that the transfer may be expected not to operate against the public interest."
Brendan Hopkins, chief executive of IN&M, said: "The acquisition enables IN&M to own the leading metropolitan newspaper group in the Northern Ireland market, and will be earnings enhancing in the present financial year."
John Taylor, deputy leader of the Ulster Unionist Party, who had led unionist concerns over the acquisition, said he was "pleased" the deal would not mean the transfer of printing or advertising jobs from Belfast to Dublin.
"We have achieved most of our objectives which we articulated in our oral evidence to the commission," he said.