The UK Immigration minister Caroline Nokes is defending her government's handling of a surge in illegal migrants crossing the English Channel.
More than 220 people have attempted the crossing in small boats since November.
Ms Nokes said Home Secretary Sajid Javid would cut short a family holiday to deal with the "major incident".
Dover MP Charlie Elphicke called for more patrol boats and accused the Home Office of letting the "crisis" escalate.
The Conservative MP said the Home Office was not taking the matter "seriously enough".
It comes after another 12 people were detained off the coast of Dover in the early hours of Friday morning UK time.
Only one of the Border Force's fleet of five cutters - specialist boats which the force describes as being capable of rescuing several migrant boats at the same time - is currently operational in the Dover Strait.
Ms Nokes said the number of patrol boats was being "constantly reviewed", but it was "feasible that were we to put additional craft they might act as a magnet - encouraging people to make a perilous crossing".
She said the UK was working with France to try to prevent migrants from setting out in the first place, and there was an "enormous" ongoing intelligence-led operation to deter people traffickers.
"It is really important to remember that we are dealing with people's lives, people who have taken a terrible, terrible risk, but that we are working with the French to find the most effective route for returns for those who it is appropriate for."
The National Crime Agency said that tackling the criminals behind these "extremely dangerous" attempted crossings was an "operational priority" and significant resources were devoted to them.
Chris Hogben, from the NCA, said its work with French colleagues had resulted in dozens of attempted crossings being prevented.
He said that over the last three weeks French colleagues have recovered at least 95 migrants including nine children, and arrested seven people caught attempting to facilitate these crossings.
He added that he anticipated further arrests in the coming weeks and thought more attempts to reach the UK were likely.
Mr Javid has appointed a "gold commander" to take overall charge of the situation and make strategic decisions about the response.
He was due to talk to his French counterpart about the situation over the weekend.
Mr Elphicke said "we need a clear strategy to defeat the traffickers", adding that the French authorities should step up action on their side of the Channel.
The people found off the Kent coast since November:
- 28 December - Twelve migrants in two separate boats detained off the coast of Dover
- 27 December - Some 23 migrants, including three children, were detained in Kent after crossing the channel in small three boats
- 26 December - Three migrants brought ashore by Border Force
- 25 December - Forty migrants, including two children, crossed the Channel in five boats
- 15 December - Four children are among a group of 11 people rescued off Dover. Eight said they were Iraqi and the other three claimed to be Iranian
- 12 December - Six men found in a dinghy off the coast of Dover
- 11 December - Six people, thought to be from Iran were rescued from a small boat off the Kent coast. A second boat with eight men, all saying they were Iranian were picked up later the same day off Dover
- 4 December - Two men were brought to shore at Dover
- 27 November - An 18-month-old baby was among nine people rescued from a dinghy off Dover
- 23 November - Eight men located in a dinghy off the coast of Dover
- 22 November - Thirteen men and one woman were intercepted in two dinghies off the coast of Dover
- 18 November - Nine suspected migrants were found clambering up rocks in Folkestone after apparently crossing the English Channel in a small boat
- 16 November - Seven suspected migrants were found off Samphire Hoe, near Dover
- 14 November - Nine suspected migrants - seven men, one woman and a toddler - were found off the Kent coast. Another 10 were found near Dover Docks and five men
- 13 November - Fourteen men and three children entered Port of Dover on a French fishing boat believed to be stolen
- 9 November -Seven men were found in the English Channel off Dover
- 3 November - Eight suspected migrants were stopped off the Kent coast and seven others were stopped at Dover Western Docks