In correspondence seen by Sky News, the Public and Commercial Services Union (PCS), which represents civil servants, has requested an urgent meeting with the Department for Business and Trade (DBT) to discuss "the legal jeopardy faced by civil servants who are continuing to work on this policy."
"Given the implications for our members, we believe there are ample grounds to immediately suspend all such work. We therefore request that you meet with us urgently to discuss this matter and cease work immediately,” said the letter, with was sent on Wednesday to the DBT.
According to the report, members of the union have asked their employers to stop giving them tasks related to arms export licenses to Israel alongside other work that may be related to Israeli crimes in the Gaza Strip.
The PCS confirmed to Sky News that it is considering legal action against the government.
The correspondence showed that the PCS has been asking relevant ministers for its legal advice on arming Israel since January, when the International Court of Justice (ICJ) issued an interim ruling imposing provisional measures on Israel to prevent acts of genocide against Palestinians in Gaza.
Paul O'Connor, head of bargaining at PCS, said the union agrees with the UN court and believes "that the UK government has an obligation to do all it can to halt the onslaught."
Pressure on the British government is mounting to cease arms exports to Israel, especially after the killing of seven food charity workers, including three UK citizens, in the Gaza Strip in an Israeli strike on Monday.

Israel has waged a deadly military offensive on the Gaza Strip since a cross-border attack in early October by the Palestinian group Hamas killed around 1,200 people.
More than 33,000 Palestinians have since been killed and 75,577 injured amid mass destruction and shortages of necessities.
Israel has also imposed a crippling blockade on the Gaza Strip, leaving its population, particularly residents of northern Gaza, on the verge of starvation.
The Israeli war has pushed 85% of Gaza’s population into internal displacement amid acute shortages of food, clean water and medicine, while 60% of the enclave's infrastructure has been damaged or destroyed, according to the UN.