The government tonight published a series of letters Jeremy Corbyn sent to ministers before he was leader of the Labour Party, in which he describes Israel’s politicians as “criminals,” calls for them to be banned from Britain and for trade sanctions to be imposed on the state.

In the letters, released following a Freedom of Information request, Corbyn advocates “penalising Israel” which, he says, treat Palestinians “with disdain,” adding that Israel’s “victimisation of the people of East Jerusalem is an abomination”.

The explosive documents, which will cause serious damage to the already-strained relations between the Labour leader and the Jewish community, include government responses, as well as Corbyn’s introduction of Palestinian figures.

In one letter to then foreign secretary William Hague in February 2013, Corbyn implored Hague “at the very least” to “stop allowing Israel’s criminal politicians to come to our country freely”.

In his second of three requests, he urged Hague to “ensure the BBC portray Palestine fairly,” chastising the national broadcaster for “barely mentioning the Palestinian hunger strike!” Finally, he asked Hague to “end the siege of Gaza.”

Corbyn later added: “Had I not been working toward all three of these aims, I’d have hung my head in shame.”

The MP for Islington North penned the emotive correspondence shortly after returning from Gaza, which he described as resembling “one huge and suffering refugee camp,” adding: “Without UNWRA [the UN’s refugee agency] as well as the illegal tunnel trade that has evolved out of desperation, no one would survive.”

The tunnels, many of which have now been destroyed, have long been used to supply Hamas militants with rockets to fire at Israeli towns and cities.

On the subject of banning Israeli politicians, he wrote: “I cannot help wondering how long successive governments are going to stand by pretending that an occupying power of so many years should be treated in the same way as the people whose land is not only occupied, but routinely confiscated.”

Elsewhere in the letter, he described the “unjustness” of Israel’s controversial administrative detention system, the “medical negligence” of Palestinian prisoners and the “death in custody after the alleged interrogation of Arafat Jarafat”.

In another fiery broadside sent to Hague in February 2012, Corbyn says: “Israel’s current actions and victimisation of the people of East Jerusalem is an abomination that is totally illegal. Surely the only logical way forward here is to penalise Israel via the most obvious method… There is clearly no time to lose to take action via the EU-Israel Association Trade Agreement.”

This call for Britain to “penalise” Israel is the clearest sign yet that Corbyn supports the aims and objectives of the Boycott, Divestment and Sanctions (BDS) movement.

In another letter to Hague, dated March 2011, Corbyn condemned the “lack of balance” in a statement from then Middle East minister Alistair Burt, regarding an escalation in violence.

Corbyn said: “He [Burt] is aware in recent days that Israeli military action has resulted in significant loss of life and injuries. He may also be aware that this recent escalation began when Israel launched a mortar shell attack on Gaza on February 23rd… So far there have been no statements on the Israeli Embassy’s website about this loss of life.” He adds that, days later, “Israel targeted civilian property”.