A now disgraced senior diplomat at the Israeli embassy in London spent several hours courting the Scottish National Party's deputy leader ahead of his official trip to Israel, raising further questions over Israel's interference in British politics, Al Jazeera's Investigative Unit can reveal.

In undercover footage recorded as part of Al Jazeera's investigation The Lobby, Shai Masot - a senior political officer at the embassy who was forced to quit after the film exposed his attempts to manipulate British politics - is seen boasting of his relationship with Angus Robertson to our undercover reporter "Robin Harrow" (alias).

"I had hours and hours with him, like I think nine hours in total of sitting around in the embassy … we had a lot of meetings and he told us a lot of stories," Masot told Robin and their companion, Maria Strizzolo, a British civil servant.

"[Robertson's] feeling really close, you know, to the Jewish people," Masot explained, adding that the SNP deputy leader "has a great trip" to Israel lined up.

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Over dinner at a Kensington brasserie, Masot recalled Robertson's story about his German heritage.

Robertson's grandfather, a politician in the Reichstag, was persecuted by the Nazis, Masot said.

After his arrest, Robertson's grandfather had his birth certificate changed to identify him as Jewish, which made him a de facto enemy of the state, Masot added.

He said that Robertson had also told him a story from Scotland's history of a 14th-century manuscript that laid claim to the Scottish nation by declaring that the Scots were in fact one of the lost tribes of Israel.

Strizzolo, who was active with the Conservative Friends of Israel parliamentary group, was clearly won over.

"I actually really like him," she said.

"Mmm ... I love Angus," Masot replied, apparently keen to let his companions know that Robertson was someone Israel could work with at a political level.

Strizzolo also resigned when The Lobby was first broadcast.

She was filmed plotting alongside Masot to "take down" Sir Alan Duncan, Britain's pro-Palestinian deputy foreign secretary.

Duncan has previously shown strong sympathies towards Palestinians who suffered under Israel's illegal occupation.

The SNP, too, has been a long-standing advocate for a Palestinian state.

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Many in the party's grassroots draw parallels with their own struggle for an independent Scotland, and decry the British government's policy towards Israel.

In the 2015 general election, the SNP's ranks swelled in Westminster. The party recorded a historic landslide victory in Scotland, winning 56 of 59 seats.

In a separate meeting, Masot told our undercover reporter that he wants grassroots pro-Israel movements to fill a "vacuum" in the SNP.

Trip to Israel

Robertson, along with fellow MPs Kirsten Oswald and Paul Monaghan, made their visit in November at the invitation of the Israeli and Palestinian ambassadors to London.

During the one-week trip, they met with Israeli and Palestinian government officials, Israeli businesses and human rights groups such as B'Tselem and Breaking the Silence.

They also visited the Palestinian Shu'fat refugee camp, UN positions in the occupied Golan Heights and the Holocaust memorial at Yad Vashem on a programme Robertson described as "extremely balanced".

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An SNP spokesperson told Al Jazeera that while the SNP Westminster Group funded the official trip, Israeli government officials were among those who provided assistance in terms of logistical support and in-country travel.

The Palestinian Authority, the UN and the Council for Arab-British Understanding provided similar assistance, the spokesperson said.

According to parliamentary rules, MPs do not have to declare overseas trips "wholly" funded by their own parties, but members must declare any hospitality and travel costs amounting to more than £300 ($375).

The nature and value of this assistance remains unclear.

Israel a successful 'start-up nation'

Speaking to The Jewish Chronicle on his return in November, Robertson praised Israel's success as a "start-up nation" and looked forward to the "huge potential" for trade and tourism with Scotland.

He also cited Israel's relationship with Jews living in the diaspora as something Scotland could learn from.

But in January, in a meeting with the Palestinian Authority's diplomatic representative to the UK, Manuel Hassassian, Robertson was critical of Israel.

According to a statement from the Palestinian embassy, Robertson said that seeing the facts on the ground had been a "sobering and depressing experience".

He also condemned plans by the government of Prime Minister Benjamin Netanyahu to expand illegal construction in the occupied West Bank.

Robertson added that he believed the term "settlement" was inappropriate because "it is a word that connotes something temporary whereas sadly they have been built and planned to be permanent".

Downplaying Masot's role

When The Lobby was broadcast in January, the Israeli embassy in London played down Masot's position, saying he was a "junior employee".

However Masot, a former major in the Israeli Navy, was not inexperienced.

At one point, Masot told undercover reporter Robin that he had applied for a job as the "head of the Foreign Affairs Department of the Intelligence Department in Israel".

An SNP spokesperson confirmed that Robertson met Masot during meetings with the Israeli ambassador in his capacity as the "ambassador’s assistant".

Masot was not among the 20 diplomats and support staff named on the embassy's official list. However, Al Jazeera has learned that Masot was instead granted a visa as one of the embassy's "technical and administrative staff".

While most embassies of a similar size usually have around two visas granted for these kind of roles, the Foreign and Commonwealth Office recently confirmed that Israel has 17.

While the British government has been quick to sweep the sensitive, counterintelligence matter under the carpet, the parliament's foreign affairs committee is taking a closer look.

Its chairman, Crispin Blunt, singled out by Masot as a supposed "Arabist" during undercover filming, has announced an inquiry into "the way that foreign states and interested parties seek to influence UK policy".