A European Union effort to launch an independent inquiry into Yemen's civl war has been dumbed down after the UK refused to support it.

The Netherlands had proposed that the UN Human Rights Council (HRC) set up an independent inquiry into civilian deaths in Yemen, but foreign secretary Boris Johnson rejected calls for Britain to support the international inquiry last week.

He insisted that the Government is "using a very, very wide variety of information sources about what is happening to acquaint ourselves with the details" about the war in Yemen, where a Saudi Arabia-led coalition is accused of committing war crimes.

In a joint open letter, Human Rights Watch and other NGOs called for the HRC to "establish an international, independent me­chanism to investigate alleged serious violations and abuses of international human rights and humanitarian law committed" in Yemen.

Footage shows extent of child malnutrition in Yemen as Britain continues to sell arms to Saudi Arabia

However, after the UK refused to lend its support, the Netherlands' proposal was watered down to suggest the Office of the UN High Commissioner for Human Rights (OHCHR) dispatch a mission to monitor the situation.

“Blocking attempts to create an international inquiry is a betrayal of the people of Yemen who have suffered so much during this conflict,” Polly Truscott of Amnesty International said.

“It’s shocking. The UK ought to be standing up for justice and accountability, not acting as a cheerleader for arms companies.”

Two senior MPs have since urged Mr Johnson to back the independent probe, saying the matter was urgent in light of the country's growing death toll.

On Friday, the OHCHR expressed "deep concern" over increasing attacks against civilians in Yemen after a total of 180 civilians were killed in one month, raising the death toll to nearly 4,000 since the conflict began in March 2015.

Cecile Pouilly at the UN agency said August also saw an increase in the number of attacks against civilian facilities including hospitals, markets, and places of worship.

Her statement came only two days after airstrikes by the Saudi-led coalition bombed houses in the Red Sea port city of Hodeidah, killing at least 32 civilians.

10 examples of Saudi Arabia's human rights abuses Show all 10 1 /10 10 examples of Saudi Arabia's human rights abuses 10 examples of Saudi Arabia's human rights abuses In October 2014, three lawyers, Dr Abdulrahman al-Subaihi, Bander al-Nogaithan and Abdulrahman al-Rumaih , were sentenced to up to eight years in prison for using Twitter to criticize the Ministry of Justice. AFP/Getty Images 10 examples of Saudi Arabia's human rights abuses In March 2015, Yemen’s Sunni President Abd-Rabbu Mansour Hadi was forced into exile after a Shia-led insurgency. A Saudi Arabia-led coalition has responded with air strikes in order to reinstate Mr Hadi. It has since been accused of committing war crimes in the country. Getty Images 10 examples of Saudi Arabia's human rights abuses Women who supported the Women2Drive campaign, launched in 2011 to challenge the ban on women driving vehicles, faced harassment and intimidation by the authorities. The government warned that women drivers would face arrest. Getty Images 10 examples of Saudi Arabia's human rights abuses Members of the Kingdom’s Shia minority, most of whom live in the oil-rich Eastern Province, continue to face discrimination that limits their access to government services and employment. Activists have received death sentences or long prison terms for their alleged participation in protests in 2011 and 2012. Getty Images 10 examples of Saudi Arabia's human rights abuses All public gatherings are prohibited under an order issued by the Interior Ministry in 2011. Those defy the ban face arrest, prosecution and imprisonment on charges such as “inciting people against the authorities”. Getty Images 10 examples of Saudi Arabia's human rights abuses In March 2014, the Interior Ministry stated that authorities had deported over 370,000 foreign migrants and that 18,000 others were in detention. Thousands of workers were returned to Somalia and other states where they were at risk of human rights abuses, with large numbers also returned to Yemen, in order to open more jobs to Saudi Arabians. Many migrants reported that prior to their deportation they had been packed into overcrowded makeshift detention facilities where they received little food and water and were abused by guards. Getty Images 10 examples of Saudi Arabia's human rights abuses The Saudi Arabian authorities continue to deny access to independent human rights organisations like Amnesty International, and they have been known to take punitive action, including through the courts, against activists and family members of victims who contact Amnesty. Getty Images 10 examples of Saudi Arabia's human rights abuses Raif Badawi was sentenced to 1000 lashes and 10 years in prison for using his liberal blog to criticise Saudi Arabia’s clerics. He has already received 50 lashes, which have reportedly left him in poor health. Carsten Koall/Getty Images 10 examples of Saudi Arabia's human rights abuses Dawood al-Marhoon was arrested aged 17 for participating in an anti-government protest. After refusing to spy on his fellow protestors, he was tortured and forced to sign a blank document that would later contain his ‘confession’. At Dawood’s trial, the prosecution requested death by crucifixion while refusing him a lawyer. Getty Images 10 examples of Saudi Arabia's human rights abuses Ali Mohammed al-Nimr was arrested in 2012 aged either 16 or 17 for participating in protests during the Arab spring. His sentence includes beheading and crucifixion. The international community has spoken out against the punishment and has called on Saudi Arabia to stop. He is the nephew of a prominent government dissident. Getty

Earlier this month leaked draft report from Britain's Committee on Arms Exports Control said Britain shoult halt its sale of weapons to Saudi Arabia while accusations of war crimes are investigated.

The committee, which comprises 16 MPs from four parties, also said it was likely British weapons had been used to violate international law.

Both the European Parliament and the House of Commons International Development Committee have already called for exports to the autocracy to stop, but the Government says it has not seen evidence of Saudi war crimes.

Tom Brake, foreign affairs spokesperson for the Liberal Democrats, said: "Again the UK Government are trying to cover up the Saudi Arabian military’s flagrant violations of international humanitarian law.

"A fully independent international enquiry is the least the people of Yemen deserve, yet instead Boris Johnson chooses to put Britain’s interests, in the form of arms exports to Saudi Arabia, over the urgent need for a full investigation into human rights' abuses.

"Under the May Government, the FCO have abandoned any pretence of an ethical foreign policy. It is all about trade and arms sales now "



Meanwhile, rebels known as Houthis have continued to tighten their siege on the city of Taiz, where they are fighting local forces aligned with the internationally-recognised government.