By Alex Stevenson Follow @alex__stevenson
The coalition is set to make the adoption process much easier, David Cameron will tell a children's centre in London later.
The prime minister is expected to outline the government's priority of "sorting out and speeding up" adoption in the UK in an attempt to ensure more children benefit from a stable family life.
Councils will be put under pressure to minimise delays in the adoption process by removing social workers' need to find a 'perfect match'.
More inter-racial adoptions will be encouraged and couples who smoke or are overweight will be considered. Mr Cameron will say it is "shocking" that black children take twice as long as white children to be adopted and pledge to break down the "absurd barriers" to mixed-race adoption.
It is hoped even couples who would not immediately be obvious choices for a child would be able to provide a better family environment than being brought up in care - an alternative which offers inferior life chances.
"There's no more urgent task for government than this. Young lives are being wasted while the process takes its toll – and the victims are some of the most vulnerable young people in our society," Mr Cameron will say.
"You can't put children's futures on hold while the system gets round to dealing with their case.
"They need help now, yet it takes more than two-and-a-half years on average for a child who enters care to be adopted."
If a match is not found within three months local authorities will be required to refer children to the national adoption register, making them available to a wider pool of potential adopters.
An adoption bill is expected to be introduced in the next parliamentary session and will be taken through parliament by education secretary Michael Gove, who was himself adopted. The government will publish its adoption action plan next week.
"However conscientious they may be, practitioners who wait too long for any particular child, holding out for a perfect parental match, are not acting in that child's best interests," he said in his speech on the issue last month.
"We need to be more flexible and encourage would-be adopters to be flexible. The child they might go on to love and cherish may not be the child they first imagined."
Labour, which had expressed concern that other permanent placements like long-term fostering and kinship placements might be more appropriate in some cases, today warned that fostering might not be a "panacea" to the problem.
"We don't need to wait for legislation on this, we could implement these reforms today with guidance and training," shadow children's minister Catherine McKinnell said.
"The government should focus on the right long-term outcomes for all children including those with more complex needs."