At least 140,000 people have fled the conflict in eastern Ukraine in the last three weeks alone, with more than a million fleeing the region in total, according to figures published by the UN.

The UN refugee agency (UNHCR) said on Tuesday that at least 260,000 people have now fled their homes to other areas within Ukraine and a further 814,000 have fled across the border to Russia since the conflict began in the areas around Donetsk and Luhansk.

However, director of UNHCR’s Europe Bureau Vincent Cochetel warned that the number may be far higher, as many people are staying with friends and relatives, and would not have been counted in the UN’s statistics, adding:

“Because of insecurity, humanitarian actors have not been able to assess the situation of people displaced in the Luhansk region”

Those who have remained in Luhansk face survival without proper supplies of food and water, and sporadic access to electricity and communications. Buildings and roads have also been severely damaged in the conflict, impeding efforts to provide humanitarian aid as Ukrainian forces continues to lay siege to the city.

Meanwhile, a war of words rages on between Russian President Vladimir Putin and Ukrainian President Petro Poroshenko, with each blaming the other for the escalating violence in eastern Ukraine.

More than 2,600 people have died in the conflict since fighting broke out in April, with thousands more injured.