Jeane Freeman said the UK s Department of Work and Pensions (DWP) has already gone back on an agreement to give Scotland the power to axe the bedroom tax next year. And she warned today that the devolution of benefits must not " slip down the list" after the delay was blamed on "other priorities" by the Westminster department.
Ms Freeman described the devolution of social security as the "single biggest handover of power" since devolution in 1999.
Holyrood is to take control of 11 benefits as part of the post-referendum deal on new powers for Holyrood. This accounts for about 15% of current social, security spend, roughly £3 million in total.
The minister claimed it would be "easier" to take control of the entire benefits system at Holyrood as the proposed hybrid set-up just leads to "complexity."
The minister also admitted that the overhaul of IT systems and infrastructure also present a major a "risk" in the transfer of powers.
"I've always said that one of the risks is how well DWP works with us and us with them," Ms Freeman said today.
"I'm not intending to imply any malicious intent by anybody but the DWP have a lot on their plate and there's a lot that they have to do and they have priorities.
"What I have to constantly make sure is that we do not slip down that priority list.
"Of course the letter that put the bedroom tax abolition back a year is a matter of concern and worry and that simply means that we need to up our efforts to be saying to the DWP to say `we have our plans, you know what they are - we need to know that you're plans to devolve those benefits to us continue to match ours in terms of the timings."
She added: "We rightly as a Scottish Government have to maintain our focus on the DWP keeping this work, this devolution of benefits, to Scotland at the top of their priority list. In this instance it has slipped."
Jeanne Freeman: Social security with dignity and respectSecretary of State for Work and Pensions Esther McVey said no agreement had been reached on 2019 when she appeared before MSPs, but this was rejected by Ms Freeman.
The minister said it will also be critical that the IT systems developed by the Scottish Government are able to interact with the DWP set-up. She said "new build" IT will be used in conjunction with existing system to minimise potential problems.
"This is a major task and there are risks in that of course," the minister said.