British Prime Minister Boris Johnson has ordered a cross-government review into the migrant crisis as he is “exasperated” by a failure to stem the number of crossings from France, The Times reported on Saturday.

British frustration at the number of migrants illegally crossing the English Channel from French shores has resurfaced in recent days after more than 1,000 refugees reached southern England in a single day last week. Some 22,000 migrants have made the crossing this year.

The Times said Johnson has drafted in cabinet office minister Stephen Barclay to oversee government attempts to find solutions and ensure departments beyond Priti Patel’s interior ministry play their part.

It said lawmakers in Johnson’s Conservative Party have warned him that the migrant crisis risks becoming a big electoral issue, undermining his pledge to control Britain’s borders.

Johnson’s Downing Street office had no immediate comment.

On Thursday French President Emmanuel Macron said Britain was oscillating “between partnership and provocation” and called for more collaboration.