( CNN ) - A senior Iranian official has welcomed UK efforts to resolve the diplomatic crisis over 15 British marines and sailors held in Iranian custody.
Iran's parliament speaker Gholamali Haddadadel told an Iranian state broadcaster's Web site that British efforts to negotiate the detainees' release were "appropriate."
"The British are trying to solve the issue of their arrested soldiers with negotiations and this is appropriate action," Haddadadel was quoted as saying.
But he added: "The British should agree to their mistake and change their behavior of before."
Haddadadel is considered an influential figure within Iran because of his connections with the country's Supreme Leader Ayatollah Ali Khamenei, to whom he is related by marriage.
Iran's President Mahmoud Ahmadinejad was expected to hold a news conference on Wednesday in which Iranian state television said he would "explain Iran's view."
Meanwhile a spokeswoman for British Prime Minister Tony Blair confirmed late on Tuesday that diplomatic moves had been made towards Tehran to secure the release of the 15 military personnel.
"The prime minister remains committed to resolving this by diplomatic means," the Downing Street spokeswoman said.
"The UK has proposed direct bilateral discussions and awaits an Iranian response on when these can begin."
On Tuesday Blair described the next two days as being "fairly critical" in an interview with a Scottish radio station and welcomed comments by Ali Larijani, the secretary of Iran's Supreme National Security, that Iran saw "no need" to put the 15 on trial."The most important thing is to get these people back," Blair told Glasgow-based Real Radio.
Larijani also told Iranian state TV on Tuesday that the two countries' foreign ministries had held talks about the standoff for the first time. (Watch how tempers have cooled in diplomatic dispute )
But Larijani told Britain's Channel 4 television that Britain must admit its military personnel intruded into Iranian territorial waters and "guarantee this violation would not be committed again."
Britain insists the sailors and marines were well inside Iraqi waters when Iran captured them on March 23.
In addition to demanding their release, Britain also wants consular access to the detainees, whose location is unknown.
Iran has released several videos showing the 14 men and one woman in which they appeared to be in good health. Iran also released videotaped confessions from four of the sailors -- including the woman, Faye Turney. (Watch the two crew members describe their 'intrusion' )
Britain said the confessions were coerced and expressed its outrage at the videos' release.
The newest images, published Tuesday by the Iranian news agency Fars, show crew members talking in a group and playing a game.
It was not immediately clear if new stills were a breach of Tehran's earlier suggestion that no more images would be published.