Relatives of UK victims of the Bali bombings in 2002 have reacted angrily after 18 people jailed over the attacks had their sentences cut.
The bombs killed people from 22 countries, including 28 Britons
Indonesia has reduced prison terms as part of a tradition of remissions for the country's Independence Day.
Conservative MP Tobias Ellwood, whose brother died, has asked the government to urge Indonesia to reconsider.
Twenty-eight Britons were among 202 people who died when two bombs exploded in the Kuta area on 12 October 2002.
One bomb hit an Irish bar on the tourist strip and the other exploded in a van outside a nearby club.
Abu Bakar Ba'asyir, a 66-year-old cleric who was convicted of conspiracy in the attacks and jailed for 30 months, was told on Wednesday his sentence would be reduced by four months and 15 days.
Seventeen other people have had their jail terms cut by three months.
Ringleaders of the attacks, who were jailed for life or sentenced to death, are not eligible for remission.
The UK Bali Bombing Victims group, which represents most of the British families, has said it is seeking an urgent meeting with the Indonesian Ambassador in London.
Mr Ellwood, MP for Bournemouth East, lost his brother Jonathan, a 37-year-old teacher from Aldbury in Hertfordshire, who was attending a conference on Bali.
He said: "It brings little comfort to us here in the UK, where our security services are doing their utmost to combat terrorism, if, when we fly abroad, we are exposed to terrorism because other countries are not matching our efforts.
"A global war on terrorism must be fought globally, otherwise terrorists will exploit those pockets of weakness."
Dan Miller, who grew up near Sevenoaks in Kent, died in the bombings and his sister Susanna Miller told the BBC: "To talk about clemency in relation to the bombs is appalling.
"They showed no clemency when they attacked so many innocent people mercilessly and it's deeply distressing to think that they may have any sort of remission.
"We as relatives will never get any sort of remission from what happened to our loved ones."
'Salt in wound'
Sue Cooper, whose brother Paul Hussey, from Hawkinge, Kent, was killed, said she felt "very upset and angry".
"... Somebody who's responsible for killing my brother and all the other people - they should rot in prison, there's no way they should ever get out," she said.
"The memories are there all the time anyway, it's something that you don't forget but this is just something else to rub salt into the wound."
Alex Braden, father of victim Daniel Braden, 28, from Brighton, said he thought all bereaved families would feel bad.
He said: "I think there is a feeling about Ba'asyir, including from ourselves, that he should be incarcerated and shouldn't be given the oxygen of publicity."