LONDON (AP) — British Prime Minister Theresa May is fighting back against critics of her Brexit deal, telling her Conservative opponents that their alternative plans for Britain’s departure from the European Union wouldn’t work.

May is battling to win over rebels in her own ranks and save her leadership, with two Cabinet ministers quitting and other Conservative critics launching a bid to oust her after Britain agreed to a divorce deal with the EU this week.

In an interview with the Daily Mail on Saturday, May said alternatives favored by her critics to tackle a key stumbling block — the issue of the Irish border — wouldn’t resolve the problem.

Disaffected “Brexiteers” believe they have the numbers required to trigger a challenge to May’s leadership within days.