Three government ministers have said the UK will “continue to press” the African country of Malawi on LGBT rights after it sentenced a couple to 14 years in jail for being gay.

The couple, Steven Monjeza, 26, and Tiwonge Chimbalanga, 20, were told by a judge today they would also serve hard labour as a warning to other gay people after being convicted of having anal sex.

A joint statement from junior Foreign Office ministers Henry Bellingham and Stephen O’Brien and junior equality minister Lynne Featherstone said they were “deeply dismayed” by the convictions and by reports the pair had suffered mistreatment in police custody.

It said: “Malawi has made significant progress on human rights in recent years. The government has signed up to international human rights treaties and Malawi’s constitution protects the rights of all its citizens. Infringement of these rights is intolerable. The conviction and sentencing to the maximum 14 years’ imprisonment of Mr Chimbalanga and Mr Monjeza, runs counter to a positive trend.

“Britain has a close and strong partnership with Malawi and it is in this spirit that we raise our concerns. The UK believes that human rights apply to everyone regardless of their sexual orientation or gender identity.

“The UK urges the government of Malawi to review its laws to ensure the defence of human rights for all, without discrimination on any grounds. The UK, along with our international partners, will continue to press the government of Malawi on this issue.”

Mr Monjeza and Mr Chimbalanga had denied the charges. They have been kept in an overcrowded jail since their arrest in December and were repeatedly refused bail.

Gay rights campaigner Peter Tatchell, who has been raising awareness of their plight, described the 14-year sentence as “brutal”.

The couple were told by magistrate Nyakwawa Usiwa that they were being given a “scaring sentence” to prevent people trying to emulate them.

Mr Tatchell said today: “This is an appalling, vindictive and brutal sentence, which tramples on Malawi’s constitution, violates personal privacy and reverses the country’s commitment to human rights.

“With so much hatred and violence in Malawi, it is sick that the court has jailed these two men for loving and caring for each other.”

Undule Mwakasungura, director of the Centre for Human Rights and Rehabilitation in South Africa told the South Africa Press Association: “This conviction and sentence raises serious concerns regarding the human rights of all individuals in Malawi … protecting human rights is not a western issue, it is a Malawian issue.”

The couple’s lawyers have said they will appeal the sentence. They previously argued for a non-custodial punishment, auguring that no one had been harmed by the couple’s actions.