The government "covered up" a malfunctioned unarmed test of Britain's Trident missile system, The Sunday Times reported.
The Trident II D5 ballistic missiles are carried by Britain's four Vanguard-class submarines, and they are able to deliver thermonuclear warheads from multiple independently-targetable re-entry vehicles (MIRVs).
In a front page article, the newspaper says that the failed test took place shortly before Theresa May became prime minister, "but she omitted any mention of the failed test when she persuaded parliament to spend 40 billion pounds on new Trident submarines in her first big Commons speech on July 18."
During the test, the unarmed missile "may have veered off in the wrong direction towards America" after being launched from a British submarine off the coast of Florida in June last year, according to the article.
However, Sky News quoted its Defence Correspondent Alistair Bunkall as saying that he had been told that the earlier report about the missile veering towards the United States is not true.
The revelation of the missile test failure has put pressure on May's government. But the prime minister did not directly respond to the issue when she was questioned by BBC.
She told BBC that she had "absolute faith" in Britain's nuclear weapons system despite reports about the failed missile test.