Displaced women and girls are facing a heightened risk of gender-based violence during the coronavirus crisis, the UN Refugee Agency said on Monday.
The UNHCR said they may be forced into "survival sex" or child marriages.
Lockdowns imposed to control the spread of Covid-19 have restricted movement and led to the closure of services.
"We need to pay urgent attention to the protection of refugee, displaced and stateless women and girls at the time of this pandemic," said Gillian Triggs, the UNHCR assistant high commissioner for protection.
"They are among those most at-risk. Doors should not be left open for abusers and no help spared for women surviving abuse and violence."
She said displaced women could end up confined with their abusers, while others, having lost their precarious livelihoods, "may be forced into survival sex, or child marriages by their families", said Ms Triggs.
The restrictions imposed in many countries in response to the coronavirus pandemic meant limited access to support services, said the UNHCR.
It said some safe shelters had been temporarily suspended.
To counter the risk, the UNHCR was distributing emergency cash to survivors and women deemed to be at risk of gender-based violence.
Ms Triggs said governments should ensure that the "rising risks of violence" for displaced women were taken into account in their Covid-19 action plans.
One measure could be ensuring that services for survivors of gender-based violence were designated as essential and remain accessible.