Mr Hall faces jail and a compensation payout of up to $10 million in civil and criminal prosecutions launched by a large Thai cannery, Natural Fruits Co.
He sees the firm's defamation action as an attempt to silence legitimate criticism of alleged migrant abuses originally revealed in a report by advocates Finnwatch. He co-authored the report.
''The British Embassy has given support to Andy Hall,'' Mr Kent said on a visit to Phuket yesterday. ''We've given all appropriate assistance.
''We think that the issue of labor rights is an important one in general and one that the UK and the European Union addresses with Thailand.
''We are looking at that in terms of the European-Thailand Free Trade Agreement as well.''
Mr Hall, 34, travels between Burma and Thailand with possible arrest a constant worry since the action began in February.
His concern was heightened when an email from the British Embassy told him that he would have to go to a Thai police station to find out more about a fresh charge.
''The claims in question relate to an interview I gave to Al Jazeera in Myanmar (Burma),'' Mr Hall told the Bangkok Post. ''This case should not be within the jurisdiction of Thai police, so they had no right to investigate and call me for questioning.''
Mr Hall said he was asked by police at Bangkok's Bangna station to sign a confession without a proper English translation.
He says this was an abuse of the justice process and is now counter-suing Bangna police for failing to properly investigate the allegations made against him.
The case is being watched closely by other international human rights advocates and particularly by the European Union delegation in Thailand.
Labor standards are of special concern with the EU also consistently advocating greater freedom of expression in Thailand.
''We are in regular contact with Andy Hall,'' Mr Kent said yesterday. ''Recently he was in London and he met colleagues in London and he met colleagues at the British Embassy.
''We've explained to him what we can and can't do. Thailand has its own legal system. Thailand is not the UK.
''Just as the Thai Embassy in London cannot play a part in the internal jurisdiction of the UK, so the British Embassy in Thailand cannot take on the role of the court.
''What we can do is to ensure that Andy Hall's rights are respected. We will stay in close contact.''