As many as 15,000 Kachin refugees are now living in the shadows on the Chinese border with no access to humanitarian aid or legal protection, according to a local support group who says that international assistance is urgently needed.

The warning comes days after China issued a quiet reprimand of the Burmese government, whose conflict with the opposition Kachin Independence Army (KIA) in the northern state triggered a flow of refugees across the border.

“The Chinese government doesn’t want to mention that Burma refugees are staying on the China side,” May Li Aung, from the Wunpawng Ning Htoi group, told DVB. “They don’t want the international community to know about it.”

As a result refugees are forced to lean on local populations, churches and poorly funded aid groups, who are struggling to meet their growing needs. May Li Aung says that civilians on the Chinese side have supported the refugee since the fighting erupted in June last year, but that “it’s difficult to collect [donations] from them again and again”.

She warned that unless help arrives soon, a food crisis could emerge. UN teams have so far only been given access to refugees sheltering in Burmese government-controlled territory, although aid convoys were permitted to make one trip late last year to the town of Laiza in Kachin state, where the KIA is headquartered and where thousands of refugees are based.

The Burmese government is reluctant to allow international organisations to assist those seeking refuge outside of its territory, fearing that the move could be seen as offering succour to armed opposition groups.

China has officially denied the existence of refugees in its country, but is known to have pressured many into returning to Burma. Beijing has also blocked the UN from visiting the border region.

“We are talking with the [Chinese] authorities to ensure that people are treated in accordance with international humanitarian standards,” Andrej Mahehic, spokesperson for the UN High Commissioner for Refugees (UNCHR), confirmed to DVB.

But in practice there is little UN agencies can do without the full cooperation of the relevant sovereign state, and the body has come under fire for not being more explicit about its inability to access refugees.

Up to 70,000 Kachin have been forced to flee since fighting broke out nine months ago, many of them heading for settlements in Yunnan province on the Chinese border. Last week China warned Burma to stem the flow of refugees or risk upsetting a normally strong relationship.

“Maintaining the peace and stability of the Chinese-Myanmar [Burma] frontier region concerns the common interests of both countries,” Reuters quoted senior official Jia Qinglin as telling visiting Burma lower house speaker Shwe Mann.

“China … sincerely hopes Myanmar will find a peaceful way to appropriately resolve problems with ethnic reconciliation and will protect the long-term peace and stability of the China-Myanmar border region,” Jia reportedly said. He added that the two Asian powers’ strategic relationship presented “unprecedented opportunities, but also challenges.”

The Kachin conflict is placing an additional strain on Burma’s relationship with China, which is already said to have suffered in the wake of its democratic reform programme. Analysts have speculated that President Thein Sein’s reform agenda is at least partly driven by a desire to cool relations with their Eastern neighbour.

His decision to suspend the controversial hydro-electric dam project in Myitsone last September is the strongest indication yet of a split. The escalating refugee crisis is an embarrassment to the Chinese and is likely to fuel the fires of discontent, as it did in 2009 when a Burmese army offensive against an ethnic Kokang militia in Shan state forced more than 30,000 refugees to flee into China.